ARM SelectDYN_ALLOC should emit a copy from SP rather than referencing SP directly. In cases where there are two dyn_alloc in the same BB it would have caused the old SP value to be reused and badness ensues. rdar://7493908
llvm is generating poor code for dynamic alloca, I'll fix that later.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101383 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMISelDAGToDAG.cpp b/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 7d48663..2f24d2e 100644
--- a/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -945,7 +945,7 @@
SDValue Chain = N->getOperand(0);
SDValue Size = N->getOperand(1);
SDValue Align = N->getOperand(2);
- SDValue SP = CurDAG->getRegister(ARM::SP, MVT::i32);
+ SDValue SP = CurDAG->getCopyFromReg(Chain, dl, ARM::SP, MVT::i32);
int32_t AlignVal = cast<ConstantSDNode>(Align)->getSExtValue();
if (AlignVal < 0)
// We need to align the stack. Use Thumb1 tAND which is the only thumb