--- a/docs/MIRLangRef.rst	Sun Dec 23 19:23:36 2018 +0900
+++ b/docs/MIRLangRef.rst	Wed Aug 14 19:46:37 2019 +0900
@@ -60,6 +60,11 @@
 
    ``llc -stop-after=machine-cp bug-trigger.ll > test.mir``
 
+If the same pass is run multiple times, a run index can be included
+after the name with a comma.
+
+   ``llc -stop-after=dead-mi-elimination,1 bug-trigger.ll > test.mir``
+
 After generating the input MIR file, you'll have to add a run line that uses
 the ``-run-pass`` option to it. In order to test the post register allocation
 pseudo instruction expansion pass on X86-64, a run line like the one shown
@@ -135,7 +140,7 @@
 - The target-specific ``MachineConstantPoolValue`` subclasses (in the ARM and
   SystemZ backends) aren't serialized at the moment.
 
-- The ``MCSymbol`` machine operands are only printed, they can't be parsed.
+- The ``MCSymbol`` machine operands don't support temporary or local symbols.
 
 - A lot of the state in ``MachineModuleInfo`` isn't serialized - only the CFI
   instructions and the variable debug information from MMI is serialized right
@@ -143,9 +148,9 @@
 
 These limitations impose restrictions on what you can test with the MIR format.
 For now, tests that would like to test some behaviour that depends on the state
-of certain ``MCSymbol``  operands or the exception handling state in MMI, can't
-use the MIR format. As well as that, tests that test some behaviour that
-depends on the state of the target specific ``MachineFunctionInfo`` or
+of temporary or local ``MCSymbol``  operands or the exception handling state in
+MMI, can't use the MIR format. As well as that, tests that test some behaviour
+that depends on the state of the target specific ``MachineFunctionInfo`` or
 ``MachineConstantPoolValue`` subclasses can't use the MIR format at the moment.
 
 High Level Structure
@@ -185,15 +190,19 @@
      name:            inc
      tracksRegLiveness: true
      liveins:
-       - { reg: '%rdi' }
+       - { reg: '$rdi' }
+     callSites:
+       - { bb: 0, offset: 3, fwdArgRegs:
+           - { arg: 0, reg: '$edi' } }
      body: |
        bb.0.entry:
-         liveins: %rdi
+         liveins: $rdi
 
-         %eax = MOV32rm %rdi, 1, _, 0, _
-         %eax = INC32r killed %eax, implicit-def dead %eflags
-         MOV32mr killed %rdi, 1, _, 0, _, %eax
-         RETQ %eax
+         $eax = MOV32rm $rdi, 1, _, 0, _
+         $eax = INC32r killed $eax, implicit-def dead $eflags
+         MOV32mr killed $rdi, 1, _, 0, _, $eax
+         CALL64pcrel32 @foo <regmask...>
+         RETQ $eax
      ...
 
 The document above consists of attributes that represent the various
@@ -205,6 +214,9 @@
 The attribute ``body`` is a `YAML block literal string`_. Its value represents
 the function's machine basic blocks and their machine instructions.
 
+The attribute ``callSites`` is a representation of call site information which
+keeps track of call instructions and registers used to transfer call arguments.
+
 Machine Instructions Format Reference
 =====================================
 
@@ -307,7 +319,7 @@
 .. code-block:: text
 
     bb.0.entry:
-      liveins: %edi, %esi
+      liveins: $edi, $esi
 
 The list of live in registers and successors can be empty. The language also
 allows multiple live in register and successor lists - they are combined into
@@ -344,7 +356,7 @@
 
 .. code-block:: text
 
-    RETQ %eax
+    RETQ $eax
 
 However, if the machine instruction has one or more explicitly defined register
 operands, the instruction's name has to be specified after them. The example
@@ -353,7 +365,7 @@
 
 .. code-block:: text
 
-    %sp, %fp, %lr = LDPXpost %sp, 2
+    $sp, $fp, $lr = LDPXpost $sp, 2
 
 The instruction names are serialized using the exact definitions from the
 target's ``*InstrInfo.td`` files, and they are case sensitive. This means that
@@ -370,11 +382,11 @@
 
 .. code-block:: text
 
-    %fp = frame-setup ADDXri %sp, 0, 0
+    $fp = frame-setup ADDXri $sp, 0, 0
 
 .. code-block:: text
 
-    %x21, %x20 = frame-destroy LDPXi %sp
+    $x21, $x20 = frame-destroy LDPXi $sp
 
 .. _registers:
 
@@ -385,9 +397,9 @@
 
 .. code-block:: text
 
-    BUNDLE implicit-def %r0, implicit-def %r1, implicit %r2 {
-      %r0 = SOME_OP %r2
-      %r1 = ANOTHER_OP internal %r0
+    BUNDLE implicit-def $r0, implicit-def $r1, implicit $r2 {
+      $r0 = SOME_OP $r2
+      $r1 = ANOTHER_OP internal $r0
     }
 
 The first instruction is often a bundle header. The instructions between ``{``
@@ -397,28 +409,28 @@
 ---------
 
 Registers are one of the key primitives in the machine instructions
-serialization language. They are primarly used in the
+serialization language. They are primarily used in the
 :ref:`register machine operands <register-operands>`,
 but they can also be used in a number of other places, like the
 :ref:`basic block's live in list <bb-liveins>`.
 
-The physical registers are identified by their name. They use the following
-syntax:
+The physical registers are identified by their name and by the '$' prefix sigil.
+They use the following syntax:
 
 .. code-block:: text
 
-    %<name>
+    $<name>
 
 The example below shows three X86 physical registers:
 
 .. code-block:: text
 
-    %eax
-    %r15
-    %eflags
+    $eax
+    $r15
+    $eflags
 
-The virtual registers are identified by their ID number. They use the following
-syntax:
+The virtual registers are identified by their ID number and by the '%' sigil.
+They use the following syntax:
 
 .. code-block:: text
 
@@ -431,7 +443,7 @@
     %0
 
 The null registers are represented using an underscore ('``_``'). They can also be
-represented using a '``%noreg``' named register, although the former syntax
+represented using a '``$noreg``' named register, although the former syntax
 is preferred.
 
 .. _machine-operands:
@@ -439,9 +451,8 @@
 Machine Operands
 ----------------
 
-There are seventeen different kinds of machine operands, and all of them, except
-the ``MCSymbol`` operand, can be serialized. The ``MCSymbol`` operands are
-just printed out - they can't be parsed back yet.
+There are seventeen different kinds of machine operands, and all of them can be
+serialized.
 
 Immediate Operands
 ^^^^^^^^^^^^^^^^^^
@@ -452,7 +463,7 @@
 
 .. code-block:: text
 
-    %eax = MOV32ri -42
+    $eax = MOV32ri -42
 
 An immediate operand is also used to represent a subregister index when the
 machine instruction has one of the following opcodes:
@@ -510,7 +521,7 @@
 
 .. code-block:: text
 
-  dead %eax = XOR32rr undef %eax, undef %eax, implicit-def dead %eflags, implicit-def %al
+  dead $eax = XOR32rr undef $eax, undef $eax, implicit-def dead $eflags, implicit-def $al
 
 .. _register-flags:
 
@@ -630,7 +641,7 @@
 
 .. code-block:: text
 
-    %rax = MOV64rm %rip, 1, _, @G, _
+    $rax = MOV64rm $rip, 1, _, @G, _
 
 The named global values are represented using an identifier with the '@' prefix.
 If the identifier doesn't match the regular expression
@@ -652,7 +663,7 @@
 
 .. code-block:: text
 
-    %sgpr2 = S_ADD_U32 _, target-index(amdgpu-constdata-start) + 8, implicit-def _, implicit-def _
+    $sgpr2 = S_ADD_U32 _, target-index(amdgpu-constdata-start) + 8, implicit-def _, implicit-def _
 
 Jump-table Index Operands
 ^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -661,7 +672,7 @@
 
 .. code-block:: text
 
-    tBR_JTr killed %r0, %jump-table.0
+    tBR_JTr killed $r0, %jump-table.0
 
 A machine jump-table entry contains a list of ``MachineBasicBlocks``. When serializing all the function's jump-table entries, the following format is used:
 
@@ -690,7 +701,7 @@
 External Symbol Operands
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 
-An external symbol operand is represented using an identifier with the ``$``
+An external symbol operand is represented using an identifier with the ``&``
 prefix. The identifier is surrounded with ""'s and escaped if it has any
 special non-printable characters in it.
 
@@ -698,7 +709,7 @@
 
 .. code-block:: text
 
-    CALL64pcrel32 $__stack_chk_fail, csr_64, implicit %rsp, implicit-def %rsp
+    CALL64pcrel32 &__stack_chk_fail, csr_64, implicit $rsp, implicit-def $rsp
 
 MCSymbol Operands
 ^^^^^^^^^^^^^^^^^
@@ -725,7 +736,7 @@
 
 .. code-block:: text
 
-    CFI_INSTRUCTION offset %w30, -16
+    CFI_INSTRUCTION offset $w30, -16
 
 which may be emitted later in the MC layer as:
 
@@ -742,7 +753,7 @@
 
 .. code-block:: text
 
-   %x0 = COPY intrinsic(@llvm.returnaddress)
+   $x0 = COPY intrinsic(@llvm.returnaddress)
 
 Predicate Operands
 ^^^^^^^^^^^^^^^^^^