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author | Hans Wennborg <hans@hanshq.net> | 2016-08-24 23:46:52 +0000 |
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committer | Hans Wennborg <hans@hanshq.net> | 2016-08-24 23:46:52 +0000 |
commit | ce25e1a77e895c7ef32c156f6cff3012f6c5a946 (patch) | |
tree | 929c80cbae502b6dd1ff3dadbbbfab797ec354fd | |
parent | 08064c20dbafddd026113eb88b49848ed6ba513a (diff) | |
download | llvm-ce25e1a77e895c7ef32c156f6cff3012f6c5a946.zip llvm-ce25e1a77e895c7ef32c156f6cff3012f6c5a946.tar.gz llvm-ce25e1a77e895c7ef32c156f6cff3012f6c5a946.tar.bz2 |
Merging r279647:llvmorg-3.9.0-rc3llvmorg-3.9.0
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r279647 | sanjoy | 2016-08-24 11:10:21 -0700 (Wed, 24 Aug 2016) | 5 lines
[SCCP] Don't delete side-effecting instructions
I'm not sure if the `!isa<CallInst>(Inst) &&
!isa<TerminatorInst>(Inst))` bit is correct either, but this fixes the
case we know is broken.
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llvm-svn: 279689
-rw-r--r-- | llvm/lib/Transforms/Scalar/SCCP.cpp | 23 | ||||
-rw-r--r-- | llvm/test/Transforms/SCCP/calltest.ll | 20 |
2 files changed, 21 insertions, 22 deletions
diff --git a/llvm/lib/Transforms/Scalar/SCCP.cpp b/llvm/lib/Transforms/Scalar/SCCP.cpp index da700f1..f74f28a 100644 --- a/llvm/lib/Transforms/Scalar/SCCP.cpp +++ b/llvm/lib/Transforms/Scalar/SCCP.cpp @@ -1538,17 +1538,6 @@ static bool tryToReplaceWithConstant(SCCPSolver &Solver, Value *V) { return true; } -static bool tryToReplaceInstWithConstant(SCCPSolver &Solver, Instruction *Inst, - bool shouldEraseFromParent) { - if (!tryToReplaceWithConstant(Solver, Inst)) - return false; - - // Delete the instruction. - if (shouldEraseFromParent) - Inst->eraseFromParent(); - return true; -} - // runSCCP() - Run the Sparse Conditional Constant Propagation algorithm, // and return true if the function was modified. // @@ -1597,8 +1586,9 @@ static bool runSCCP(Function &F, const DataLayout &DL, if (Inst->getType()->isVoidTy() || isa<TerminatorInst>(Inst)) continue; - if (tryToReplaceInstWithConstant(Solver, Inst, - true /* shouldEraseFromParent */)) { + if (tryToReplaceWithConstant(Solver, Inst)) { + if (isInstructionTriviallyDead(Inst)) + Inst->eraseFromParent(); // Hey, we just changed something! MadeChanges = true; ++NumInstRemoved; @@ -1789,10 +1779,9 @@ static bool runIPSCCP(Module &M, const DataLayout &DL, Instruction *Inst = &*BI++; if (Inst->getType()->isVoidTy()) continue; - if (tryToReplaceInstWithConstant( - Solver, Inst, - !isa<CallInst>(Inst) && - !isa<TerminatorInst>(Inst) /* shouldEraseFromParent */)) { + if (tryToReplaceWithConstant(Solver, Inst)) { + if (!isa<CallInst>(Inst) && !isa<TerminatorInst>(Inst)) + Inst->eraseFromParent(); // Hey, we just changed something! MadeChanges = true; ++IPNumInstRemoved; diff --git a/llvm/test/Transforms/SCCP/calltest.ll b/llvm/test/Transforms/SCCP/calltest.ll index 9dec22f..a6c2606 100644 --- a/llvm/test/Transforms/SCCP/calltest.ll +++ b/llvm/test/Transforms/SCCP/calltest.ll @@ -1,12 +1,16 @@ -; RUN: opt < %s -sccp -loop-deletion -simplifycfg -S | not grep br +; RUN: opt < %s -sccp -loop-deletion -simplifycfg -S | FileCheck %s +declare double @sqrt(double) readnone nounwind +%empty = type {} +declare %empty @has_side_effects() + +define double @test_0(i32 %param) { +; CHECK-LABEL: @test_0( +; CHECK-NOT: br +entry: ; No matter how hard you try, sqrt(1.0) is always 1.0. This allows the ; optimizer to delete this loop. -declare double @sqrt(double) - -define double @test(i32 %param) { -entry: br label %Loop Loop: ; preds = %Loop, %entry %I2 = phi i32 [ 0, %entry ], [ %I3, %Loop ] ; <i32> [#uses=1] @@ -19,3 +23,9 @@ Exit: ; preds = %Loop ret double %V } +define i32 @test_1() { +; CHECK-LABEL: @test_1( +; CHECK: call %empty @has_side_effects() + %1 = call %empty @has_side_effects() + ret i32 0 +} |