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authorPawel Wodnicki <pawel@32bitmicro.com>2012-11-26 16:52:27 +0000
committerPawel Wodnicki <pawel@32bitmicro.com>2012-11-26 16:52:27 +0000
commitbc69dc1d880792c0c2bbea189c3dbb2c39505391 (patch)
treea46f0619346bac6516b4b5fe547d46fc48cd0bdd
parent077cee586eda8b0edcca1ff07e823104eff718e7 (diff)
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Merging r168196: into the 3.2 release branch.
Make this easier to understand, as suggested by Chandler. git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_32@168594 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r--lib/Analysis/InstructionSimplify.cpp7
-rw-r--r--lib/Transforms/InstCombine/InstCombineCompares.cpp7
2 files changed, 12 insertions, 2 deletions
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index c24c18f807..a76e5ad1b8 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -2067,15 +2067,20 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
// Determine Y and Z in the form icmp (X+Y), (X+Z).
Value *Y, *Z;
if (A == C) {
+ // C + B == C + D -> B == D
Y = B;
Z = D;
} else if (A == D) {
+ // D + B == C + D -> B == C
Y = B;
Z = C;
} else if (B == C) {
+ // A + C == C + D -> A == D
Y = A;
Z = D;
- } else if (B == D) {
+ } else {
+ assert(B == D);
+ // A + D == C + D -> A == C
Y = A;
Z = C;
}
diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp
index e223a049f0..7c3f8fe15d 100644
--- a/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -2358,15 +2358,20 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
// Determine Y and Z in the form icmp (X+Y), (X+Z).
Value *Y, *Z;
if (A == C) {
+ // C + B == C + D -> B == D
Y = B;
Z = D;
} else if (A == D) {
+ // D + B == C + D -> B == C
Y = B;
Z = C;
} else if (B == C) {
+ // A + C == C + D -> A == D
Y = A;
Z = D;
- } else if (B == D) {
+ } else {
+ assert(B == D);
+ // A + D == C + D -> A == C
Y = A;
Z = C;
}