Fix a typo in ValueTracking that's causing instcombine to delete needed shift instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98416 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index 92cbb7c..5ae72f7 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -779,7 +779,7 @@
for (unsigned i = 1, e = PN->getNumIncomingValues(); i != e; ++i) {
if (Tmp == 1) return Tmp;
Tmp = std::min(Tmp,
- ComputeNumSignBits(PN->getIncomingValue(1), TD, Depth+1));
+ ComputeNumSignBits(PN->getIncomingValue(i), TD, Depth+1));
}
return Tmp;
}
diff --git a/test/Transforms/InstCombine/shift-sra.ll b/test/Transforms/InstCombine/shift-sra.ll
index 58f3226..a578bbe 100644
--- a/test/Transforms/InstCombine/shift-sra.ll
+++ b/test/Transforms/InstCombine/shift-sra.ll
@@ -56,3 +56,23 @@
; CHECK: %P = phi i64
; CHECK-NEXT: ret i64 %P
}
+
+; rdar://7732987
+define i32 @test5(i32 %Y) {
+ br i1 undef, label %A, label %C
+A:
+ br i1 undef, label %B, label %D
+B:
+ br label %D
+C:
+ br i1 undef, label %D, label %E
+D:
+ %P = phi i32 [0, %A], [0, %B], [%Y, %C]
+ %S = ashr i32 %P, 16
+ ret i32 %S
+; CHECK: @test5
+; CHECK: %P = phi i32
+; CHECK-NEXT: ashr i32 %P, 16
+E:
+ ret i32 0
+}