[PeepholeOptimizer] Update the kill flags when extending the live-range of the
source of a copy.
<rdar://problem/12702965>
llvm-svn: 216229
diff --git a/llvm/lib/CodeGen/PeepholeOptimizer.cpp b/llvm/lib/CodeGen/PeepholeOptimizer.cpp
index ae14331..98fcc2e 100644
--- a/llvm/lib/CodeGen/PeepholeOptimizer.cpp
+++ b/llvm/lib/CodeGen/PeepholeOptimizer.cpp
@@ -899,7 +899,11 @@
if (!findNextSource(NewSrc, NewSubReg) || SrcReg == NewSrc)
continue;
// Rewrite source.
- Changed |= CpyRewriter->RewriteCurrentSource(NewSrc, NewSubReg);
+ if (CpyRewriter->RewriteCurrentSource(NewSrc, NewSubReg)) {
+ // We may have extended the live-range of NewSrc, account for that.
+ MRI->clearKillFlags(NewSrc);
+ Changed = true;
+ }
}
// TODO: We could have a clean-up method to tidy the instruction.
// E.g., v0 = INSERT_SUBREG v1, v1.sub0, sub0