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| author | Dan Gohman <gohman@apple.com> | 2010-08-13 21:17:19 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2010-08-13 21:17:19 +0000 |
| commit | 1e393466e1595ccfe44de466a8db570a44db8c8b (patch) | |
| tree | dc35402fc8bd831d70d0944220a9930458d18e93 /lib | |
| parent | a5fc53b5f4d6e5f39c3e646629a8503658253870 (diff) | |
| download | external_llvm-1e393466e1595ccfe44de466a8db570a44db8c8b.zip external_llvm-1e393466e1595ccfe44de466a8db570a44db8c8b.tar.gz external_llvm-1e393466e1595ccfe44de466a8db570a44db8c8b.tar.bz2 | |
Fix LSR's ExtractImmediate and ExtractSymbol to avoid calling
ScalarEvolution::getAddExpr, which can be pretty expensive, when nothing
has changed, which is pretty common.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111042 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Transforms/Scalar/LoopStrengthReduce.cpp | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp index f7b22a0..a040e8a 100644 --- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -505,12 +505,14 @@ static int64_t ExtractImmediate(const SCEV *&S, ScalarEvolution &SE) { } else if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(S)) { SmallVector<const SCEV *, 8> NewOps(Add->op_begin(), Add->op_end()); int64_t Result = ExtractImmediate(NewOps.front(), SE); - S = SE.getAddExpr(NewOps); + if (Result != 0) + S = SE.getAddExpr(NewOps); return Result; } else if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(S)) { SmallVector<const SCEV *, 8> NewOps(AR->op_begin(), AR->op_end()); int64_t Result = ExtractImmediate(NewOps.front(), SE); - S = SE.getAddRecExpr(NewOps, AR->getLoop()); + if (Result != 0) + S = SE.getAddRecExpr(NewOps, AR->getLoop()); return Result; } return 0; @@ -528,12 +530,14 @@ static GlobalValue *ExtractSymbol(const SCEV *&S, ScalarEvolution &SE) { } else if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(S)) { SmallVector<const SCEV *, 8> NewOps(Add->op_begin(), Add->op_end()); GlobalValue *Result = ExtractSymbol(NewOps.back(), SE); - S = SE.getAddExpr(NewOps); + if (Result) + S = SE.getAddExpr(NewOps); return Result; } else if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(S)) { SmallVector<const SCEV *, 8> NewOps(AR->op_begin(), AR->op_end()); GlobalValue *Result = ExtractSymbol(NewOps.front(), SE); - S = SE.getAddRecExpr(NewOps, AR->getLoop()); + if (Result) + S = SE.getAddRecExpr(NewOps, AR->getLoop()); return Result; } return 0; |