Handle getresult instructions in different basic blocks

from their aggregate operands by moving the getresult
instructions.

llvm-svn: 48657

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp b/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
index 8762d3dd1bc..43251c344f8 100644
--- a/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -1127,6 +1127,15 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
             // Sink address computing for memory operands into the block.
             MadeChange |= OptimizeInlineAsmInst(I, &(*CI), SunkAddrs);
         }
+    } else if (GetResultInst *GRI = dyn_cast<GetResultInst>(I)) {
+      // Ensure that all getresult instructions live in the same basic block
+      // as their associated struct-value instructions. Codegen requires
+      // this, as lowering only works on one basic block at a time.
+      if (Instruction *Agg = dyn_cast<Instruction>(GRI->getAggregateValue())) {
+        BasicBlock *AggBB = Agg->getParent();
+        if (AggBB != GRI->getParent())
+          GRI->moveBefore(AggBB->getTerminator());
+      }
     }
   }