diff options
| author | Shuxin Yang <shuxin.llvm@gmail.com> | 2013-01-10 23:32:01 +0000 |
|---|---|---|
| committer | Shuxin Yang <shuxin.llvm@gmail.com> | 2013-01-10 23:32:01 +0000 |
| commit | 253449db20f86b655852a397245ba16ff262452f (patch) | |
| tree | 19a6a9e95b5f8fe231cffccba48b5c115492a6ca | |
| parent | 582e4f278b95d50a45c6f56e33da5e78c19afc17 (diff) | |
PR14904: Segmentation fault running pass 'Recognize loop idioms'
The root cause is mistakenly taking for granted that
"dyn_cast<Instruction>(a-Value)"
return a non-NULL instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172145 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Transforms/Scalar/LoopIdiomRecognize.cpp | 2 | ||||
| -rw-r--r-- | test/Transforms/LoopIdiom/X86/popcnt.ll | 20 |
2 files changed, 21 insertions, 1 deletions
diff --git a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp index c4f90125ac..8258719a02 100644 --- a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp +++ b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp @@ -407,7 +407,7 @@ bool NclPopcountRecognize::detectIdiom(Instruction *&CntInst, // step 2: detect instructions corresponding to "x2 = x1 & (x1 - 1)" { - if (DefX2->getOpcode() != Instruction::And) + if (!DefX2 || DefX2->getOpcode() != Instruction::And) return false; BinaryOperator *SubOneOp; diff --git a/test/Transforms/LoopIdiom/X86/popcnt.ll b/test/Transforms/LoopIdiom/X86/popcnt.ll index 2f458fb2f1..25df93d3a0 100644 --- a/test/Transforms/LoopIdiom/X86/popcnt.ll +++ b/test/Transforms/LoopIdiom/X86/popcnt.ll @@ -118,3 +118,23 @@ while.end: ; preds = %while.body, %entry %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ] ret i32 %c.0.lcssa } + +define i32 @PopCntCrash3(i64 %a, i32 %x) { +entry: + %tobool3 = icmp eq i64 %a, 0 + %cmp = icmp eq i32 %x, 0 + br i1 %tobool3, label %while.end, label %while.body + +while.body: ; preds = %entry, %while.body + %c.05 = phi i32 [ %inc, %while.body ], [ 0, %entry ] + %a.addr.04 = phi i64 [ %and, %while.body ], [ %a, %entry ] + %inc = add nsw i32 %c.05, 1 + %sub = add i64 %a.addr.04, -1 + %and = and i64 %sub, %a.addr.04 + %tobool = icmp eq i64 %and, 0 + br i1 %cmp, label %while.end, label %while.body + +while.end: ; preds = %while.body, %entry + %c.0.lcssa = phi i32 [ 0, %entry ], [ %inc, %while.body ] + ret i32 %c.0.lcssa +} |