CbC/CbC_llvm: lib/CodeGen/EarlyIfConversion.cpp annotate

annotate lib/CodeGen/EarlyIfConversion.cpp @ 134:3a76565eade5 LLVM5.0.1

update 5.0.1

author	mir3636
date	Sat, 17 Feb 2018 09:57:20 +0900
parents	803732b1fca8
children	c2174574ed3a

rev	line source
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	1 //===-- EarlyIfConversion.cpp - If-conversion on SSA form machine code ----===//
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	2 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	3 // The LLVM Compiler Infrastructure
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	4 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	5 // This file is distributed under the University of Illinois Open Source
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	6 // License. See LICENSE.TXT for details.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	7 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	8 //===----------------------------------------------------------------------===//
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	9 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	10 // Early if-conversion is for out-of-order CPUs that don't have a lot of
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	11 // predicable instructions. The goal is to eliminate conditional branches that
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	12 // may mispredict.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	13 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	14 // Instructions from both sides of the branch are executed specutatively, and a
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	15 // cmov instruction selects the result.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	16 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	17 //===----------------------------------------------------------------------===//
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	18
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	19 #include "llvm/ADT/BitVector.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	20 #include "llvm/ADT/PostOrderIterator.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	21 #include "llvm/ADT/SetVector.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	22 #include "llvm/ADT/SmallPtrSet.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	23 #include "llvm/ADT/SparseSet.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	24 #include "llvm/ADT/Statistic.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	25 #include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	26 #include "llvm/CodeGen/MachineDominators.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	27 #include "llvm/CodeGen/MachineFunction.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	28 #include "llvm/CodeGen/MachineFunctionPass.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	29 #include "llvm/CodeGen/MachineLoopInfo.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	30 #include "llvm/CodeGen/MachineRegisterInfo.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	31 #include "llvm/CodeGen/MachineTraceMetrics.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	32 #include "llvm/CodeGen/Passes.h"
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	33 #include "llvm/CodeGen/TargetInstrInfo.h"
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	34 #include "llvm/CodeGen/TargetRegisterInfo.h"
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	35 #include "llvm/CodeGen/TargetSubtargetInfo.h"
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	36 #include "llvm/Support/CommandLine.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	37 #include "llvm/Support/Debug.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	38 #include "llvm/Support/raw_ostream.h"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	39
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	40 using namespace llvm;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	41
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	42 #define DEBUG_TYPE "early-ifcvt"
54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	43
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	44 // Absolute maximum number of instructions allowed per speculated block.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	45 // This bypasses all other heuristics, so it should be set fairly high.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	46 static cl::opt<unsigned>
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	47 BlockInstrLimit("early-ifcvt-limit", cl::init(30), cl::Hidden,
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	48 cl::desc("Maximum number of instructions per speculated block."));
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	49
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	50 // Stress testing mode - disable heuristics.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	51 static cl::opt<bool> Stress("stress-early-ifcvt", cl::Hidden,
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	52 cl::desc("Turn all knobs to 11"));
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	53
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	54 STATISTIC(NumDiamondsSeen, "Number of diamonds");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	55 STATISTIC(NumDiamondsConv, "Number of diamonds converted");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	56 STATISTIC(NumTrianglesSeen, "Number of triangles");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	57 STATISTIC(NumTrianglesConv, "Number of triangles converted");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	58
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	59 //===----------------------------------------------------------------------===//
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	60 // SSAIfConv
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	61 //===----------------------------------------------------------------------===//
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	62 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	63 // The SSAIfConv class performs if-conversion on SSA form machine code after
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	64 // determining if it is possible. The class contains no heuristics; external
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	65 // code should be used to determine when if-conversion is a good idea.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	66 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	67 // SSAIfConv can convert both triangles and diamonds:
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	68 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	69 // Triangle: Head Diamond: Head
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	70 // \| \ / \_
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	71 // \| \ / \|
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	72 // \| [TF]BB FBB TBB
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	73 // \| / \ /
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	74 // \| / \ /
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	75 // Tail Tail
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	76 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	77 // Instructions in the conditional blocks TBB and/or FBB are spliced into the
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	78 // Head block, and phis in the Tail block are converted to select instructions.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	79 //
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	80 namespace {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	81 class SSAIfConv {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	82 const TargetInstrInfo *TII;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	83 const TargetRegisterInfo *TRI;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	84 MachineRegisterInfo *MRI;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	85
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	86 public:
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	87 /// The block containing the conditional branch.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	88 MachineBasicBlock *Head;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	89
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	90 /// The block containing phis after the if-then-else.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	91 MachineBasicBlock *Tail;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	92
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	93 /// The 'true' conditional block as determined by AnalyzeBranch.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	94 MachineBasicBlock *TBB;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	95
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	96 /// The 'false' conditional block as determined by AnalyzeBranch.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	97 MachineBasicBlock *FBB;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	98
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	99 /// isTriangle - When there is no 'else' block, either TBB or FBB will be
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	100 /// equal to Tail.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	101 bool isTriangle() const { return TBB == Tail \|\| FBB == Tail; }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	102
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	103 /// Returns the Tail predecessor for the True side.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	104 MachineBasicBlock *getTPred() const { return TBB == Tail ? Head : TBB; }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	105
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	106 /// Returns the Tail predecessor for the False side.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	107 MachineBasicBlock *getFPred() const { return FBB == Tail ? Head : FBB; }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	108
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	109 /// Information about each phi in the Tail block.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	110 struct PHIInfo {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	111 MachineInstr *PHI;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	112 unsigned TReg, FReg;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	113 // Latencies from Cond+Branch, TReg, and FReg to DstReg.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	114 int CondCycles, TCycles, FCycles;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	115
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	116 PHIInfo(MachineInstr *phi)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	117 : PHI(phi), TReg(0), FReg(0), CondCycles(0), TCycles(0), FCycles(0) {}
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	118 };
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	119
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	120 SmallVector<PHIInfo, 8> PHIs;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	121
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	122 private:
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	123 /// The branch condition determined by AnalyzeBranch.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	124 SmallVector<MachineOperand, 4> Cond;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	125
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	126 /// Instructions in Head that define values used by the conditional blocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	127 /// The hoisted instructions must be inserted after these instructions.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	128 SmallPtrSet<MachineInstr*, 8> InsertAfter;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	129
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	130 /// Register units clobbered by the conditional blocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	131 BitVector ClobberedRegUnits;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	132
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	133 // Scratch pad for findInsertionPoint.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	134 SparseSet<unsigned> LiveRegUnits;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	135
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	136 /// Insertion point in Head for speculatively executed instructions form TBB
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	137 /// and FBB.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	138 MachineBasicBlock::iterator InsertionPoint;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	139
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	140 /// Return true if all non-terminator instructions in MBB can be safely
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	141 /// speculated.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	142 bool canSpeculateInstrs(MachineBasicBlock *MBB);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	143
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	144 /// Find a valid insertion point in Head.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	145 bool findInsertionPoint();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	146
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	147 /// Replace PHI instructions in Tail with selects.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	148 void replacePHIInstrs();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	149
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	150 /// Insert selects and rewrite PHI operands to use them.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	151 void rewritePHIOperands();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	152
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	153 public:
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	154 /// runOnMachineFunction - Initialize per-function data structures.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	155 void runOnMachineFunction(MachineFunction &MF) {
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	156 TII = MF.getSubtarget().getInstrInfo();
54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	157 TRI = MF.getSubtarget().getRegisterInfo();
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	158 MRI = &MF.getRegInfo();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	159 LiveRegUnits.clear();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	160 LiveRegUnits.setUniverse(TRI->getNumRegUnits());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	161 ClobberedRegUnits.clear();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	162 ClobberedRegUnits.resize(TRI->getNumRegUnits());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	163 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	164
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	165 /// canConvertIf - If the sub-CFG headed by MBB can be if-converted,
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	166 /// initialize the internal state, and return true.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	167 bool canConvertIf(MachineBasicBlock *MBB);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	168
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	169 /// convertIf - If-convert the last block passed to canConvertIf(), assuming
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	170 /// it is possible. Add any erased blocks to RemovedBlocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	171 void convertIf(SmallVectorImpl<MachineBasicBlock*> &RemovedBlocks);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	172 };
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	173 } // end anonymous namespace
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	174
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	175
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	176 /// canSpeculateInstrs - Returns true if all the instructions in MBB can safely
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	177 /// be speculated. The terminators are not considered.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	178 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	179 /// If instructions use any values that are defined in the head basic block,
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	180 /// the defining instructions are added to InsertAfter.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	181 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	182 /// Any clobbered regunits are added to ClobberedRegUnits.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	183 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	184 bool SSAIfConv::canSpeculateInstrs(MachineBasicBlock *MBB) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	185 // Reject any live-in physregs. It's probably CPSR/EFLAGS, and very hard to
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	186 // get right.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	187 if (!MBB->livein_empty()) {
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	188 DEBUG(dbgs() << printMBBReference(*MBB) << " has live-ins.\n");
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	189 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	190 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	191
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	192 unsigned InstrCount = 0;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	193
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	194 // Check all instructions, except the terminators. It is assumed that
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	195 // terminators never have side effects or define any used register values.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	196 for (MachineBasicBlock::iterator I = MBB->begin(),
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	197 E = MBB->getFirstTerminator(); I != E; ++I) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	198 if (I->isDebugValue())
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	199 continue;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	200
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	201 if (++InstrCount > BlockInstrLimit && !Stress) {
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	202 DEBUG(dbgs() << printMBBReference(*MBB) << " has more than "
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	203 << BlockInstrLimit << " instructions.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	204 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	205 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	206
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	207 // There shouldn't normally be any phis in a single-predecessor block.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	208 if (I->isPHI()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	209 DEBUG(dbgs() << "Can't hoist: " << *I);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	210 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	211 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	212
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	213 // Don't speculate loads. Note that it may be possible and desirable to
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	214 // speculate GOT or constant pool loads that are guaranteed not to trap,
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	215 // but we don't support that for now.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	216 if (I->mayLoad()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	217 DEBUG(dbgs() << "Won't speculate load: " << *I);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	218 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	219 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	220
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	221 // We never speculate stores, so an AA pointer isn't necessary.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	222 bool DontMoveAcrossStore = true;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	223 if (!I->isSafeToMove(nullptr, DontMoveAcrossStore)) {
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	224 DEBUG(dbgs() << "Can't speculate: " << *I);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	225 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	226 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	227
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	228 // Check for any dependencies on Head instructions.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	229 for (const MachineOperand &MO : I->operands()) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	230 if (MO.isRegMask()) {
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	231 DEBUG(dbgs() << "Won't speculate regmask: " << *I);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	232 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	233 }
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	234 if (!MO.isReg())
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	235 continue;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	236 unsigned Reg = MO.getReg();
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	237
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	238 // Remember clobbered regunits.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	239 if (MO.isDef() && TargetRegisterInfo::isPhysicalRegister(Reg))
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	240 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	241 ClobberedRegUnits.set(*Units);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	242
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	243 if (!MO.readsReg() \|\| !TargetRegisterInfo::isVirtualRegister(Reg))
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	244 continue;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	245 MachineInstr *DefMI = MRI->getVRegDef(Reg);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	246 if (!DefMI \|\| DefMI->getParent() != Head)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	247 continue;
83 60c9769439b8 LLVM 3.7 Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp> parents: 77 diff changeset	248 if (InsertAfter.insert(DefMI).second)
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	249 DEBUG(dbgs() << printMBBReference(MBB) << " depends on " << DefMI);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	250 if (DefMI->isTerminator()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	251 DEBUG(dbgs() << "Can't insert instructions below terminator.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	252 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	253 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	254 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	255 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	256 return true;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	257 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	258
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	259
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	260 /// Find an insertion point in Head for the speculated instructions. The
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	261 /// insertion point must be:
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	262 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	263 /// 1. Before any terminators.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	264 /// 2. After any instructions in InsertAfter.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	265 /// 3. Not have any clobbered regunits live.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	266 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	267 /// This function sets InsertionPoint and returns true when successful, it
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	268 /// returns false if no valid insertion point could be found.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	269 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	270 bool SSAIfConv::findInsertionPoint() {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	271 // Keep track of live regunits before the current position.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	272 // Only track RegUnits that are also in ClobberedRegUnits.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	273 LiveRegUnits.clear();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	274 SmallVector<unsigned, 8> Reads;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	275 MachineBasicBlock::iterator FirstTerm = Head->getFirstTerminator();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	276 MachineBasicBlock::iterator I = Head->end();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	277 MachineBasicBlock::iterator B = Head->begin();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	278 while (I != B) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	279 --I;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	280 // Some of the conditional code depends in I.
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	281 if (InsertAfter.count(&*I)) {
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	282 DEBUG(dbgs() << "Can't insert code after " << *I);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	283 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	284 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	285
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	286 // Update live regunits.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	287 for (const MachineOperand &MO : I->operands()) {
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	288 // We're ignoring regmask operands. That is conservatively correct.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	289 if (!MO.isReg())
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	290 continue;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	291 unsigned Reg = MO.getReg();
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	292 if (!TargetRegisterInfo::isPhysicalRegister(Reg))
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	293 continue;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	294 // I clobbers Reg, so it isn't live before I.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	295 if (MO.isDef())
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	296 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	297 LiveRegUnits.erase(*Units);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	298 // Unless I reads Reg.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	299 if (MO.readsReg())
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	300 Reads.push_back(Reg);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	301 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	302 // Anything read by I is live before I.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	303 while (!Reads.empty())
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	304 for (MCRegUnitIterator Units(Reads.pop_back_val(), TRI); Units.isValid();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	305 ++Units)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	306 if (ClobberedRegUnits.test(*Units))
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	307 LiveRegUnits.insert(*Units);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	308
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	309 // We can't insert before a terminator.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	310 if (I != FirstTerm && I->isTerminator())
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	311 continue;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	312
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	313 // Some of the clobbered registers are live before I, not a valid insertion
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	314 // point.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	315 if (!LiveRegUnits.empty()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	316 DEBUG({
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	317 dbgs() << "Would clobber";
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	318 for (SparseSet<unsigned>::const_iterator
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	319 i = LiveRegUnits.begin(), e = LiveRegUnits.end(); i != e; ++i)
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	320 dbgs() << ' ' << printRegUnit(*i, TRI);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	321 dbgs() << " live before " << *I;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	322 });
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	323 continue;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	324 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	325
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	326 // This is a valid insertion point.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	327 InsertionPoint = I;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	328 DEBUG(dbgs() << "Can insert before " << *I);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	329 return true;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	330 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	331 DEBUG(dbgs() << "No legal insertion point found.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	332 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	333 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	334
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	335
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	336
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	337 /// canConvertIf - analyze the sub-cfg rooted in MBB, and return true if it is
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	338 /// a potential candidate for if-conversion. Fill out the internal state.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	339 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	340 bool SSAIfConv::canConvertIf(MachineBasicBlock *MBB) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	341 Head = MBB;
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	342 TBB = FBB = Tail = nullptr;
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	343
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	344 if (Head->succ_size() != 2)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	345 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	346 MachineBasicBlock *Succ0 = Head->succ_begin()[0];
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	347 MachineBasicBlock *Succ1 = Head->succ_begin()[1];
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	348
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	349 // Canonicalize so Succ0 has MBB as its single predecessor.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	350 if (Succ0->pred_size() != 1)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	351 std::swap(Succ0, Succ1);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	352
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	353 if (Succ0->pred_size() != 1 \|\| Succ0->succ_size() != 1)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	354 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	355
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	356 Tail = Succ0->succ_begin()[0];
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	357
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	358 // This is not a triangle.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	359 if (Tail != Succ1) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	360 // Check for a diamond. We won't deal with any critical edges.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	361 if (Succ1->pred_size() != 1 \|\| Succ1->succ_size() != 1 \|\|
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	362 Succ1->succ_begin()[0] != Tail)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	363 return false;
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	364 DEBUG(dbgs() << "\nDiamond: " << printMBBReference(*Head) << " -> "
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	365 << printMBBReference(*Succ0) << "/"
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	366 << printMBBReference(*Succ1) << " -> "
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	367 << printMBBReference(*Tail) << '\n');
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	368
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	369 // Live-in physregs are tricky to get right when speculating code.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	370 if (!Tail->livein_empty()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	371 DEBUG(dbgs() << "Tail has live-ins.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	372 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	373 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	374 } else {
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	375 DEBUG(dbgs() << "\nTriangle: " << printMBBReference(*Head) << " -> "
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	376 << printMBBReference(*Succ0) << " -> "
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	377 << printMBBReference(*Tail) << '\n');
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	378 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	379
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	380 // This is a triangle or a diamond.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	381 // If Tail doesn't have any phis, there must be side effects.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	382 if (Tail->empty() \|\| !Tail->front().isPHI()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	383 DEBUG(dbgs() << "No phis in tail.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	384 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	385 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	386
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	387 // The branch we're looking to eliminate must be analyzable.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	388 Cond.clear();
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	389 if (TII->analyzeBranch(*Head, TBB, FBB, Cond)) {
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	390 DEBUG(dbgs() << "Branch not analyzable.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	391 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	392 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	393
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	394 // This is weird, probably some sort of degenerate CFG.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	395 if (!TBB) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	396 DEBUG(dbgs() << "AnalyzeBranch didn't find conditional branch.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	397 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	398 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	399
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	400 // AnalyzeBranch doesn't set FBB on a fall-through branch.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	401 // Make sure it is always set.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	402 FBB = TBB == Succ0 ? Succ1 : Succ0;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	403
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	404 // Any phis in the tail block must be convertible to selects.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	405 PHIs.clear();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	406 MachineBasicBlock *TPred = getTPred();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	407 MachineBasicBlock *FPred = getFPred();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	408 for (MachineBasicBlock::iterator I = Tail->begin(), E = Tail->end();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	409 I != E && I->isPHI(); ++I) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	410 PHIs.push_back(&*I);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	411 PHIInfo &PI = PHIs.back();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	412 // Find PHI operands corresponding to TPred and FPred.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	413 for (unsigned i = 1; i != PI.PHI->getNumOperands(); i += 2) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	414 if (PI.PHI->getOperand(i+1).getMBB() == TPred)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	415 PI.TReg = PI.PHI->getOperand(i).getReg();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	416 if (PI.PHI->getOperand(i+1).getMBB() == FPred)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	417 PI.FReg = PI.PHI->getOperand(i).getReg();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	418 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	419 assert(TargetRegisterInfo::isVirtualRegister(PI.TReg) && "Bad PHI");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	420 assert(TargetRegisterInfo::isVirtualRegister(PI.FReg) && "Bad PHI");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	421
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	422 // Get target information.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	423 if (!TII->canInsertSelect(*Head, Cond, PI.TReg, PI.FReg,
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	424 PI.CondCycles, PI.TCycles, PI.FCycles)) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	425 DEBUG(dbgs() << "Can't convert: " << *PI.PHI);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	426 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	427 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	428 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	429
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	430 // Check that the conditional instructions can be speculated.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	431 InsertAfter.clear();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	432 ClobberedRegUnits.reset();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	433 if (TBB != Tail && !canSpeculateInstrs(TBB))
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	434 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	435 if (FBB != Tail && !canSpeculateInstrs(FBB))
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	436 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	437
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	438 // Try to find a valid insertion point for the speculated instructions in the
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	439 // head basic block.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	440 if (!findInsertionPoint())
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	441 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	442
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	443 if (isTriangle())
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	444 ++NumTrianglesSeen;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	445 else
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	446 ++NumDiamondsSeen;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	447 return true;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	448 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	449
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	450 /// replacePHIInstrs - Completely replace PHI instructions with selects.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	451 /// This is possible when the only Tail predecessors are the if-converted
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	452 /// blocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	453 void SSAIfConv::replacePHIInstrs() {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	454 assert(Tail->pred_size() == 2 && "Cannot replace PHIs");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	455 MachineBasicBlock::iterator FirstTerm = Head->getFirstTerminator();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	456 assert(FirstTerm != Head->end() && "No terminators");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	457 DebugLoc HeadDL = FirstTerm->getDebugLoc();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	458
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	459 // Convert all PHIs to select instructions inserted before FirstTerm.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	460 for (unsigned i = 0, e = PHIs.size(); i != e; ++i) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	461 PHIInfo &PI = PHIs[i];
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	462 DEBUG(dbgs() << "If-converting " << *PI.PHI);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	463 unsigned DstReg = PI.PHI->getOperand(0).getReg();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	464 TII->insertSelect(*Head, FirstTerm, HeadDL, DstReg, Cond, PI.TReg, PI.FReg);
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	465 DEBUG(dbgs() << " --> " << *std::prev(FirstTerm));
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	466 PI.PHI->eraseFromParent();
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	467 PI.PHI = nullptr;
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	468 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	469 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	470
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	471 /// rewritePHIOperands - When there are additional Tail predecessors, insert
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	472 /// select instructions in Head and rewrite PHI operands to use the selects.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	473 /// Keep the PHI instructions in Tail to handle the other predecessors.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	474 void SSAIfConv::rewritePHIOperands() {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	475 MachineBasicBlock::iterator FirstTerm = Head->getFirstTerminator();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	476 assert(FirstTerm != Head->end() && "No terminators");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	477 DebugLoc HeadDL = FirstTerm->getDebugLoc();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	478
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	479 // Convert all PHIs to select instructions inserted before FirstTerm.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	480 for (unsigned i = 0, e = PHIs.size(); i != e; ++i) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	481 PHIInfo &PI = PHIs[i];
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	482 unsigned DstReg = 0;
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	483
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	484 DEBUG(dbgs() << "If-converting " << *PI.PHI);
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	485 if (PI.TReg == PI.FReg) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	486 // We do not need the select instruction if both incoming values are
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	487 // equal.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	488 DstReg = PI.TReg;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	489 } else {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	490 unsigned PHIDst = PI.PHI->getOperand(0).getReg();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	491 DstReg = MRI->createVirtualRegister(MRI->getRegClass(PHIDst));
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	492 TII->insertSelect(*Head, FirstTerm, HeadDL,
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	493 DstReg, Cond, PI.TReg, PI.FReg);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	494 DEBUG(dbgs() << " --> " << *std::prev(FirstTerm));
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	495 }
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	496
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	497 // Rewrite PHI operands TPred -> (DstReg, Head), remove FPred.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	498 for (unsigned i = PI.PHI->getNumOperands(); i != 1; i -= 2) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	499 MachineBasicBlock *MBB = PI.PHI->getOperand(i-1).getMBB();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	500 if (MBB == getTPred()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	501 PI.PHI->getOperand(i-1).setMBB(Head);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	502 PI.PHI->getOperand(i-2).setReg(DstReg);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	503 } else if (MBB == getFPred()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	504 PI.PHI->RemoveOperand(i-1);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	505 PI.PHI->RemoveOperand(i-2);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	506 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	507 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	508 DEBUG(dbgs() << " --> " << *PI.PHI);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	509 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	510 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	511
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	512 /// convertIf - Execute the if conversion after canConvertIf has determined the
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	513 /// feasibility.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	514 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	515 /// Any basic blocks erased will be added to RemovedBlocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	516 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	517 void SSAIfConv::convertIf(SmallVectorImpl<MachineBasicBlock*> &RemovedBlocks) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	518 assert(Head && Tail && TBB && FBB && "Call canConvertIf first.");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	519
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	520 // Update statistics.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	521 if (isTriangle())
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	522 ++NumTrianglesConv;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	523 else
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	524 ++NumDiamondsConv;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	525
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	526 // Move all instructions into Head, except for the terminators.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	527 if (TBB != Tail)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	528 Head->splice(InsertionPoint, TBB, TBB->begin(), TBB->getFirstTerminator());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	529 if (FBB != Tail)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	530 Head->splice(InsertionPoint, FBB, FBB->begin(), FBB->getFirstTerminator());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	531
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	532 // Are there extra Tail predecessors?
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	533 bool ExtraPreds = Tail->pred_size() != 2;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	534 if (ExtraPreds)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	535 rewritePHIOperands();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	536 else
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	537 replacePHIInstrs();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	538
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	539 // Fix up the CFG, temporarily leave Head without any successors.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	540 Head->removeSuccessor(TBB);
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	541 Head->removeSuccessor(FBB, true);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	542 if (TBB != Tail)
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	543 TBB->removeSuccessor(Tail, true);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	544 if (FBB != Tail)
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	545 FBB->removeSuccessor(Tail, true);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	546
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	547 // Fix up Head's terminators.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	548 // It should become a single branch or a fallthrough.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	549 DebugLoc HeadDL = Head->getFirstTerminator()->getDebugLoc();
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	550 TII->removeBranch(*Head);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	551
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	552 // Erase the now empty conditional blocks. It is likely that Head can fall
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	553 // through to Tail, and we can join the two blocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	554 if (TBB != Tail) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	555 RemovedBlocks.push_back(TBB);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	556 TBB->eraseFromParent();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	557 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	558 if (FBB != Tail) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	559 RemovedBlocks.push_back(FBB);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	560 FBB->eraseFromParent();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	561 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	562
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	563 assert(Head->succ_empty() && "Additional head successors?");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	564 if (!ExtraPreds && Head->isLayoutSuccessor(Tail)) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	565 // Splice Tail onto the end of Head.
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	566 DEBUG(dbgs() << "Joining tail " << printMBBReference(*Tail) << " into head "
3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	567 << printMBBReference(*Head) << '\n');
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	568 Head->splice(Head->end(), Tail,
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	569 Tail->begin(), Tail->end());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	570 Head->transferSuccessorsAndUpdatePHIs(Tail);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	571 RemovedBlocks.push_back(Tail);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	572 Tail->eraseFromParent();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	573 } else {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	574 // We need a branch to Tail, let code placement work it out later.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	575 DEBUG(dbgs() << "Converting to unconditional branch.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	576 SmallVector<MachineOperand, 0> EmptyCond;
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	577 TII->insertBranch(*Head, Tail, nullptr, EmptyCond, HeadDL);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	578 Head->addSuccessor(Tail);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	579 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	580 DEBUG(dbgs() << *Head);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	581 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	582
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	583
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	584 //===----------------------------------------------------------------------===//
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	585 // EarlyIfConverter Pass
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	586 //===----------------------------------------------------------------------===//
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	587
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	588 namespace {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	589 class EarlyIfConverter : public MachineFunctionPass {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	590 const TargetInstrInfo *TII;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	591 const TargetRegisterInfo *TRI;
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	592 MCSchedModel SchedModel;
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	593 MachineRegisterInfo *MRI;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	594 MachineDominatorTree *DomTree;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	595 MachineLoopInfo *Loops;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	596 MachineTraceMetrics *Traces;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	597 MachineTraceMetrics::Ensemble *MinInstr;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	598 SSAIfConv IfConv;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	599
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	600 public:
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	601 static char ID;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	602 EarlyIfConverter() : MachineFunctionPass(ID) {}
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	603 void getAnalysisUsage(AnalysisUsage &AU) const override;
54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	604 bool runOnMachineFunction(MachineFunction &MF) override;
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	605 StringRef getPassName() const override { return "Early If-Conversion"; }
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	606
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	607 private:
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	608 bool tryConvertIf(MachineBasicBlock*);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	609 void updateDomTree(ArrayRef<MachineBasicBlock*> Removed);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	610 void updateLoops(ArrayRef<MachineBasicBlock*> Removed);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	611 void invalidateTraces();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	612 bool shouldConvertIf();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	613 };
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	614 } // end anonymous namespace
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	615
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	616 char EarlyIfConverter::ID = 0;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	617 char &llvm::EarlyIfConverterID = EarlyIfConverter::ID;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	618
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	619 INITIALIZE_PASS_BEGIN(EarlyIfConverter, DEBUG_TYPE,
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	620 "Early If Converter", false, false)
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	621 INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	622 INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	623 INITIALIZE_PASS_DEPENDENCY(MachineTraceMetrics)
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	624 INITIALIZE_PASS_END(EarlyIfConverter, DEBUG_TYPE,
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	625 "Early If Converter", false, false)
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	626
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	627 void EarlyIfConverter::getAnalysisUsage(AnalysisUsage &AU) const {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	628 AU.addRequired<MachineBranchProbabilityInfo>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	629 AU.addRequired<MachineDominatorTree>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	630 AU.addPreserved<MachineDominatorTree>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	631 AU.addRequired<MachineLoopInfo>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	632 AU.addPreserved<MachineLoopInfo>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	633 AU.addRequired<MachineTraceMetrics>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	634 AU.addPreserved<MachineTraceMetrics>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	635 MachineFunctionPass::getAnalysisUsage(AU);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	636 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	637
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	638 /// Update the dominator tree after if-conversion erased some blocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	639 void EarlyIfConverter::updateDomTree(ArrayRef<MachineBasicBlock*> Removed) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	640 // convertIf can remove TBB, FBB, and Tail can be merged into Head.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	641 // TBB and FBB should not dominate any blocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	642 // Tail children should be transferred to Head.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	643 MachineDomTreeNode *HeadNode = DomTree->getNode(IfConv.Head);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	644 for (unsigned i = 0, e = Removed.size(); i != e; ++i) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	645 MachineDomTreeNode *Node = DomTree->getNode(Removed[i]);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	646 assert(Node != HeadNode && "Cannot erase the head node");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	647 while (Node->getNumChildren()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	648 assert(Node->getBlock() == IfConv.Tail && "Unexpected children");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	649 DomTree->changeImmediateDominator(Node->getChildren().back(), HeadNode);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	650 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	651 DomTree->eraseNode(Removed[i]);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	652 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	653 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	654
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	655 /// Update LoopInfo after if-conversion.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	656 void EarlyIfConverter::updateLoops(ArrayRef<MachineBasicBlock*> Removed) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	657 if (!Loops)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	658 return;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	659 // If-conversion doesn't change loop structure, and it doesn't mess with back
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	660 // edges, so updating LoopInfo is simply removing the dead blocks.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	661 for (unsigned i = 0, e = Removed.size(); i != e; ++i)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	662 Loops->removeBlock(Removed[i]);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	663 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	664
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	665 /// Invalidate MachineTraceMetrics before if-conversion.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	666 void EarlyIfConverter::invalidateTraces() {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	667 Traces->verifyAnalysis();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	668 Traces->invalidate(IfConv.Head);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	669 Traces->invalidate(IfConv.Tail);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	670 Traces->invalidate(IfConv.TBB);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	671 Traces->invalidate(IfConv.FBB);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	672 Traces->verifyAnalysis();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	673 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	674
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	675 // Adjust cycles with downward saturation.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	676 static unsigned adjCycles(unsigned Cyc, int Delta) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	677 if (Delta < 0 && Cyc + Delta > Cyc)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	678 return 0;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	679 return Cyc + Delta;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	680 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	681
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	682 /// Apply cost model and heuristics to the if-conversion in IfConv.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	683 /// Return true if the conversion is a good idea.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	684 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	685 bool EarlyIfConverter::shouldConvertIf() {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	686 // Stress testing mode disables all cost considerations.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	687 if (Stress)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	688 return true;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	689
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	690 if (!MinInstr)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	691 MinInstr = Traces->getEnsemble(MachineTraceMetrics::TS_MinInstrCount);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	692
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	693 MachineTraceMetrics::Trace TBBTrace = MinInstr->getTrace(IfConv.getTPred());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	694 MachineTraceMetrics::Trace FBBTrace = MinInstr->getTrace(IfConv.getFPred());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	695 DEBUG(dbgs() << "TBB: " << TBBTrace << "FBB: " << FBBTrace);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	696 unsigned MinCrit = std::min(TBBTrace.getCriticalPath(),
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	697 FBBTrace.getCriticalPath());
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	698
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	699 // Set a somewhat arbitrary limit on the critical path extension we accept.
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	700 unsigned CritLimit = SchedModel.MispredictPenalty/2;
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	701
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	702 // If-conversion only makes sense when there is unexploited ILP. Compute the
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	703 // maximum-ILP resource length of the trace after if-conversion. Compare it
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	704 // to the shortest critical path.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	705 SmallVector<const MachineBasicBlock*, 1> ExtraBlocks;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	706 if (IfConv.TBB != IfConv.Tail)
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	707 ExtraBlocks.push_back(IfConv.TBB);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	708 unsigned ResLength = FBBTrace.getResourceLength(ExtraBlocks);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	709 DEBUG(dbgs() << "Resource length " << ResLength
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	710 << ", minimal critical path " << MinCrit << '\n');
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	711 if (ResLength > MinCrit + CritLimit) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	712 DEBUG(dbgs() << "Not enough available ILP.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	713 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	714 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	715
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	716 // Assume that the depth of the first head terminator will also be the depth
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	717 // of the select instruction inserted, as determined by the flag dependency.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	718 // TBB / FBB data dependencies may delay the select even more.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	719 MachineTraceMetrics::Trace HeadTrace = MinInstr->getTrace(IfConv.Head);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	720 unsigned BranchDepth =
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	721 HeadTrace.getInstrCycles(*IfConv.Head->getFirstTerminator()).Depth;
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	722 DEBUG(dbgs() << "Branch depth: " << BranchDepth << '\n');
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	723
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	724 // Look at all the tail phis, and compute the critical path extension caused
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	725 // by inserting select instructions.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	726 MachineTraceMetrics::Trace TailTrace = MinInstr->getTrace(IfConv.Tail);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	727 for (unsigned i = 0, e = IfConv.PHIs.size(); i != e; ++i) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	728 SSAIfConv::PHIInfo &PI = IfConv.PHIs[i];
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	729 unsigned Slack = TailTrace.getInstrSlack(*PI.PHI);
1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	730 unsigned MaxDepth = Slack + TailTrace.getInstrCycles(*PI.PHI).Depth;
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	731 DEBUG(dbgs() << "Slack " << Slack << ":\t" << *PI.PHI);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	732
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	733 // The condition is pulled into the critical path.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	734 unsigned CondDepth = adjCycles(BranchDepth, PI.CondCycles);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	735 if (CondDepth > MaxDepth) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	736 unsigned Extra = CondDepth - MaxDepth;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	737 DEBUG(dbgs() << "Condition adds " << Extra << " cycles.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	738 if (Extra > CritLimit) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	739 DEBUG(dbgs() << "Exceeds limit of " << CritLimit << '\n');
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	740 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	741 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	742 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	743
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	744 // The TBB value is pulled into the critical path.
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	745 unsigned TDepth = adjCycles(TBBTrace.getPHIDepth(*PI.PHI), PI.TCycles);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	746 if (TDepth > MaxDepth) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	747 unsigned Extra = TDepth - MaxDepth;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	748 DEBUG(dbgs() << "TBB data adds " << Extra << " cycles.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	749 if (Extra > CritLimit) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	750 DEBUG(dbgs() << "Exceeds limit of " << CritLimit << '\n');
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	751 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	752 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	753 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	754
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	755 // The FBB value is pulled into the critical path.
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	756 unsigned FDepth = adjCycles(FBBTrace.getPHIDepth(*PI.PHI), PI.FCycles);
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	757 if (FDepth > MaxDepth) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	758 unsigned Extra = FDepth - MaxDepth;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	759 DEBUG(dbgs() << "FBB data adds " << Extra << " cycles.\n");
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	760 if (Extra > CritLimit) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	761 DEBUG(dbgs() << "Exceeds limit of " << CritLimit << '\n');
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	762 return false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	763 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	764 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	765 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	766 return true;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	767 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	768
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	769 /// Attempt repeated if-conversion on MBB, return true if successful.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	770 ///
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	771 bool EarlyIfConverter::tryConvertIf(MachineBasicBlock *MBB) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	772 bool Changed = false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	773 while (IfConv.canConvertIf(MBB) && shouldConvertIf()) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	774 // If-convert MBB and update analyses.
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	775 invalidateTraces();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	776 SmallVector<MachineBasicBlock*, 4> RemovedBlocks;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	777 IfConv.convertIf(RemovedBlocks);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	778 Changed = true;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	779 updateDomTree(RemovedBlocks);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	780 updateLoops(RemovedBlocks);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	781 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	782 return Changed;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	783 }
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	784
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	785 bool EarlyIfConverter::runOnMachineFunction(MachineFunction &MF) {
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	786 DEBUG(dbgs() << "******** EARLY IF-CONVERSION ********\n"
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	787 << "********** Function: " << MF.getName() << '\n');
134 3a76565eade5 update 5.0.1 mir3636 parents: 121 diff changeset	788 if (skipFunction(MF.getFunction()))
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	789 return false;
1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	790
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	791 // Only run if conversion if the target wants it.
83 60c9769439b8 LLVM 3.7 Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp> parents: 77 diff changeset	792 const TargetSubtargetInfo &STI = MF.getSubtarget();
60c9769439b8 LLVM 3.7 Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp> parents: 77 diff changeset	793 if (!STI.enableEarlyIfConversion())
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	794 return false;
54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	795
83 60c9769439b8 LLVM 3.7 Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp> parents: 77 diff changeset	796 TII = STI.getInstrInfo();
60c9769439b8 LLVM 3.7 Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp> parents: 77 diff changeset	797 TRI = STI.getRegisterInfo();
60c9769439b8 LLVM 3.7 Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp> parents: 77 diff changeset	798 SchedModel = STI.getSchedModel();
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	799 MRI = &MF.getRegInfo();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	800 DomTree = &getAnalysis<MachineDominatorTree>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	801 Loops = getAnalysisIfAvailable<MachineLoopInfo>();
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	802 Traces = &getAnalysis<MachineTraceMetrics>();
77 54457678186b LLVM 3.6 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 0 diff changeset	803 MinInstr = nullptr;
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	804
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	805 bool Changed = false;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	806 IfConv.runOnMachineFunction(MF);
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	807
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	808 // Visit blocks in dominator tree post-order. The post-order enables nested
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	809 // if-conversion in a single pass. The tryConvertIf() function may erase
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	810 // blocks, but only blocks dominated by the head block. This makes it safe to
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	811 // update the dominator tree while the post-order iterator is still active.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	812 for (auto DomNode : post_order(DomTree))
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: 83 diff changeset	813 if (tryConvertIf(DomNode->getBlock()))
0 95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	814 Changed = true;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	815
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	816 return Changed;
95c75e76d11b LLVM 3.4 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	817 }

Mercurial > hg > CbC > CbC_llvm

annotate lib/CodeGen/EarlyIfConversion.cpp @ 134:3a76565eade5 LLVM5.0.1