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authorAlexander Kornienko <alexfh@google.com>2013-03-26 02:28:59 +0000
committerAlexander Kornienko <alexfh@google.com>2013-03-26 02:28:59 +0000
commitd934545ae6a00aa8a8179a93d11cbd93a5240849 (patch)
treeab44db08aa63a8f94a3e09d6491c4156c624af96 /lib/Transforms/InstCombine/InstCombineCompares.cpp
parent868d4470cdfa9472353ea2a49a6c456ddae9c95b (diff)
parentc204410d6bc435e7cb8ea768759a54135e8e92b5 (diff)
Updating branches/google/testing to r177703testing
git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/google/testing@177985 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineCompares.cpp')
-rw-r--r--lib/Transforms/InstCombine/InstCombineCompares.cpp7
1 files changed, 4 insertions, 3 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp
index bad46b4dab..32fdb9b708 100644
--- a/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -1333,13 +1333,14 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
}
// Transform (icmp pred iM (shl iM %v, N), CI)
- // -> (icmp pred i(M-N) (trunc %v iM to i(N-N)), (trunc (CI>>N))
- // Transform the shl to a trunc if (trunc (CI>>N)) has no loss.
+ // -> (icmp pred i(M-N) (trunc %v iM to i(M-N)), (trunc (CI>>N))
+ // Transform the shl to a trunc if (trunc (CI>>N)) has no loss and M-N.
// This enables to get rid of the shift in favor of a trunc which can be
// free on the target. It has the additional benefit of comparing to a
// smaller constant, which will be target friendly.
unsigned Amt = ShAmt->getLimitedValue(TypeBits-1);
- if (Amt != 0 && RHSV.countTrailingZeros() >= Amt) {
+ if (LHSI->hasOneUse() &&
+ Amt != 0 && RHSV.countTrailingZeros() >= Amt) {
Type *NTy = IntegerType::get(ICI.getContext(), TypeBits - Amt);
Constant *NCI = ConstantExpr::getTrunc(
ConstantExpr::getAShr(RHS,