MIR Serialization: Change MIR syntax - use custom syntax for MBBs.
This commit modifies the way the machine basic blocks are serialized - now the
machine basic blocks are serialized using a custom syntax instead of relying on
YAML primitives. Instead of using YAML mappings to represent the individual
machine basic blocks in a machine function's body, the new syntax uses a single
YAML block scalar which contains all of the machine basic blocks and
instructions for that function.
This is an example of a function's body that uses the old syntax:
body:
- id: 0
name: entry
instructions:
- '%eax = MOV32r0 implicit-def %eflags'
- 'RETQ %eax'
...
The same body is now written like this:
body: |
bb.0.entry:
%eax = MOV32r0 implicit-def %eflags
RETQ %eax
...
This syntax change is motivated by the fact that the bundled machine
instructions didn't map that well to the old syntax which was using a single
YAML sequence to store all of the machine instructions in a block. The bundled
machine instructions internally use flags like BundledPred and BundledSucc to
determine the bundles, and serializing them as MI flags using the old syntax
would have had a negative impact on the readability and the ease of editing
for MIR files. The new syntax allows me to serialize the bundled machine
instructions using a block construct without relying on the internal flags,
for example:
BUNDLE implicit-def dead %itstate, implicit-def %s1 ... {
t2IT 1, 24, implicit-def %itstate
%s1 = VMOVS killed %s0, 1, killed %cpsr, implicit killed %itstate
}
This commit also converts the MIR testcases to the new syntax. I developed
a script that can convert from the old syntax to the new one. I will post the
script on the llvm-commits mailing list in the thread for this commit.
llvm-svn: 244982
diff --git a/llvm/test/CodeGen/MIR/Generic/machine-function.mir b/llvm/test/CodeGen/MIR/Generic/machine-function.mir
index afd10ab..1c4ca3d 100644
--- a/llvm/test/CodeGen/MIR/Generic/machine-function.mir
+++ b/llvm/test/CodeGen/MIR/Generic/machine-function.mir
@@ -27,8 +27,8 @@
# CHECK-NEXT: hasInlineAsm: false
# CHECK: ...
name: foo
-body:
- - id: 0
+body: |
+ bb.0:
...
---
# CHECK: name: bar
@@ -37,8 +37,8 @@
# CHECK-NEXT: hasInlineAsm: false
# CHECK: ...
name: bar
-body:
- - id: 0
+body: |
+ bb.0:
...
---
# CHECK: name: func
@@ -48,8 +48,8 @@
# CHECK: ...
name: func
alignment: 8
-body:
- - id: 0
+body: |
+ bb.0:
...
---
# CHECK: name: func2
@@ -61,6 +61,6 @@
alignment: 16
exposesReturnsTwice: true
hasInlineAsm: true
-body:
- - id: 0
+body: |
+ bb.0:
...