[llvm-branch-commits] [llvm-branch] r142545 - in /llvm/branches/release_30: ./ include/llvm/Instructions.h lib/Transforms/InstCombine/InstructionCombining.cpp lib/VMCore/Instructions.cpp test/Transforms/InstCombine/canonicalize_branch.ll
Bill Wendling
isanbard at gmail.com
Wed Oct 19 15:11:55 PDT 2011
Author: void
Date: Wed Oct 19 17:11:55 2011
New Revision: 142545
URL: http://llvm.org/viewvc/llvm-project?rev=142545&view=rev
Log:
Merging r142168:
------------------------------------------------------------------------
r142168 | chandlerc | 2011-10-16 18:11:57 -0700 (Sun, 16 Oct 2011) | 8 lines
Add a routine to swap branch instruction operands, and update any
profile metadata at the same time. Use it to preserve metadata attached
to a branch when re-writing it in InstCombine.
Add metadata to the canonicalize_branch InstCombine test, and check that
it is tranformed correctly.
Reviewed by Nick Lewycky!
------------------------------------------------------------------------
Modified:
llvm/branches/release_30/ (props changed)
llvm/branches/release_30/include/llvm/Instructions.h
llvm/branches/release_30/lib/Transforms/InstCombine/InstructionCombining.cpp
llvm/branches/release_30/lib/VMCore/Instructions.cpp
llvm/branches/release_30/test/Transforms/InstCombine/canonicalize_branch.ll
Propchange: llvm/branches/release_30/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Wed Oct 19 17:11:55 2011
@@ -1,3 +1,3 @@
/llvm/branches/Apple/Pertwee:110850,110961
/llvm/branches/type-system-rewrite:133420-134817
-/llvm/trunk:142039,142055,142058,142112,142123,142125,142165,142243,142482,142486,142489,142537
+/llvm/trunk:142039,142055,142058,142112,142123,142125,142165,142168,142243,142482,142486,142489,142537
Modified: llvm/branches/release_30/include/llvm/Instructions.h
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_30/include/llvm/Instructions.h?rev=142545&r1=142544&r2=142545&view=diff
==============================================================================
--- llvm/branches/release_30/include/llvm/Instructions.h (original)
+++ llvm/branches/release_30/include/llvm/Instructions.h Wed Oct 19 17:11:55 2011
@@ -2367,6 +2367,13 @@
*(&Op<-1>() - idx) = (Value*)NewSucc;
}
+ /// \brief Swap the successors of this branch instruction.
+ ///
+ /// Swaps the successors of the branch instruction. This also swaps any
+ /// branch weight metadata associated with the instruction so that it
+ /// continues to map correctly to each operand.
+ void swapSuccessors();
+
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const BranchInst *) { return true; }
static inline bool classof(const Instruction *I) {
Modified: llvm/branches/release_30/lib/Transforms/InstCombine/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_30/lib/Transforms/InstCombine/InstructionCombining.cpp?rev=142545&r1=142544&r2=142545&view=diff
==============================================================================
--- llvm/branches/release_30/lib/Transforms/InstCombine/InstructionCombining.cpp (original)
+++ llvm/branches/release_30/lib/Transforms/InstCombine/InstructionCombining.cpp Wed Oct 19 17:11:55 2011
@@ -1190,8 +1190,7 @@
!isa<Constant>(X)) {
// Swap Destinations and condition...
BI.setCondition(X);
- BI.setSuccessor(0, FalseDest);
- BI.setSuccessor(1, TrueDest);
+ BI.swapSuccessors();
return &BI;
}
@@ -1206,8 +1205,7 @@
Cond->setPredicate(FCmpInst::getInversePredicate(FPred));
// Swap Destinations and condition.
- BI.setSuccessor(0, FalseDest);
- BI.setSuccessor(1, TrueDest);
+ BI.swapSuccessors();
Worklist.Add(Cond);
return &BI;
}
@@ -1223,8 +1221,7 @@
ICmpInst *Cond = cast<ICmpInst>(BI.getCondition());
Cond->setPredicate(ICmpInst::getInversePredicate(IPred));
// Swap Destinations and condition.
- BI.setSuccessor(0, FalseDest);
- BI.setSuccessor(1, TrueDest);
+ BI.swapSuccessors();
Worklist.Add(Cond);
return &BI;
}
Modified: llvm/branches/release_30/lib/VMCore/Instructions.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_30/lib/VMCore/Instructions.cpp?rev=142545&r1=142544&r2=142545&view=diff
==============================================================================
--- llvm/branches/release_30/lib/VMCore/Instructions.cpp (original)
+++ llvm/branches/release_30/lib/VMCore/Instructions.cpp Wed Oct 19 17:11:55 2011
@@ -785,6 +785,27 @@
SubclassOptionalData = BI.SubclassOptionalData;
}
+void BranchInst::swapSuccessors() {
+ assert(isConditional() &&
+ "Cannot swap successors of an unconditional branch");
+ Op<-1>().swap(Op<-2>());
+
+ // Update profile metadata if present and it matches our structural
+ // expectations.
+ MDNode *ProfileData = getMetadata(LLVMContext::MD_prof);
+ if (!ProfileData || ProfileData->getNumOperands() != 3)
+ return;
+
+ // The first operand is the name. Fetch them backwards and build a new one.
+ Value *Ops[] = {
+ ProfileData->getOperand(0),
+ ProfileData->getOperand(2),
+ ProfileData->getOperand(1)
+ };
+ setMetadata(LLVMContext::MD_prof,
+ MDNode::get(ProfileData->getContext(), Ops));
+}
+
BasicBlock *BranchInst::getSuccessorV(unsigned idx) const {
return getSuccessor(idx);
}
Modified: llvm/branches/release_30/test/Transforms/InstCombine/canonicalize_branch.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_30/test/Transforms/InstCombine/canonicalize_branch.ll?rev=142545&r1=142544&r2=142545&view=diff
==============================================================================
--- llvm/branches/release_30/test/Transforms/InstCombine/canonicalize_branch.ll (original)
+++ llvm/branches/release_30/test/Transforms/InstCombine/canonicalize_branch.ll Wed Oct 19 17:11:55 2011
@@ -1,8 +1,23 @@
; RUN: opt < %s -instcombine -S | FileCheck %s
+; Test an already canonical branch to make sure we don't flip those.
+define i32 @test0(i32 %X, i32 %Y) {
+ %C = icmp eq i32 %X, %Y
+ br i1 %C, label %T, label %F, !prof !0
+
+; CHECK: @test0
+; CHECK: %C = icmp eq i32 %X, %Y
+; CHECK: br i1 %C, label %T, label %F
+
+T:
+ ret i32 12
+F:
+ ret i32 123
+}
+
define i32 @test1(i32 %X, i32 %Y) {
%C = icmp ne i32 %X, %Y
- br i1 %C, label %T, label %F
+ br i1 %C, label %T, label %F, !prof !1
; CHECK: @test1
; CHECK: %C = icmp eq i32 %X, %Y
@@ -16,7 +31,7 @@
define i32 @test2(i32 %X, i32 %Y) {
%C = icmp ule i32 %X, %Y
- br i1 %C, label %T, label %F
+ br i1 %C, label %T, label %F, !prof !2
; CHECK: @test2
; CHECK: %C = icmp ugt i32 %X, %Y
@@ -30,7 +45,7 @@
define i32 @test3(i32 %X, i32 %Y) {
%C = icmp uge i32 %X, %Y
- br i1 %C, label %T, label %F
+ br i1 %C, label %T, label %F, !prof !3
; CHECK: @test3
; CHECK: %C = icmp ult i32 %X, %Y
@@ -42,3 +57,13 @@
ret i32 123
}
+!0 = metadata !{metadata !"branch_weights", i32 1, i32 2}
+!1 = metadata !{metadata !"branch_weights", i32 3, i32 4}
+!2 = metadata !{metadata !"branch_weights", i32 5, i32 6}
+!3 = metadata !{metadata !"branch_weights", i32 7, i32 8}
+; Base case shouldn't change.
+; CHECK: !0 = {{.*}} i32 1, i32 2}
+; Ensure that the branch metadata is reversed to match the reversals above.
+; CHECK: !1 = {{.*}} i32 4, i32 3}
+; CHECK: !2 = {{.*}} i32 6, i32 5}
+; CHECK: !3 = {{.*}} i32 8, i32 7}
More information about the llvm-branch-commits
mailing list