ARM: make sure we keep inline asm operands tied.

When patching inlineasm nodes to use GPRPair for 64-bit values, we
were dropping the information that two operands were tied, which
effectively broke the live-interval of vregs affected.

llvm-svn: 188643

2 files changed, 13 insertions, 1 deletions

diff --git a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 4ca3af6b3ea..3298b73dad2 100644
--- a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -3614,7 +3614,10 @@ SDNode *ARMDAGToDAGISel::SelectInlineAsm(SDNode *N){
     if(PairedReg.getNode()) {
       OpChanged[OpChanged.size() -1 ] = true;
       Flag = InlineAsm::getFlagWord(Kind, 1 /* RegNum*/);
-      Flag = InlineAsm::getFlagWordForRegClass(Flag, ARM::GPRPairRegClassID);
+      if (IsTiedToChangedOp)
+        Flag = InlineAsm::getFlagWordForMatchingOp(Flag, DefIdx);
+      else
+        Flag = InlineAsm::getFlagWordForRegClass(Flag, ARM::GPRPairRegClassID);
       // Replace the current flag.
       AsmNodeOperands[AsmNodeOperands.size() -1] = CurDAG->getTargetConstant(
           Flag, MVT::i32);
diff --git a/llvm/test/CodeGen/ARM/inlineasm-64bit.ll b/llvm/test/CodeGen/ARM/inlineasm-64bit.ll
index b23db106320..69b3860305f 100644
--- a/llvm/test/CodeGen/ARM/inlineasm-64bit.ll
+++ b/llvm/test/CodeGen/ARM/inlineasm-64bit.ll
@@ -85,3 +85,12 @@ define void @strd_test(i64* %p, i32 %lo, i32 %hi) nounwind {
   tail call void asm sideeffect "strd $0, ${0:H}, [$1]", "r,r"(i64 %4, i64* %p) nounwind
   ret void
 }
+
+; Make sure we don't untie operands by mistake.
+define i64 @tied_64bit_test(i64 %in) nounwind {
+; CHECK-LABEL: tied_64bit_test:
+; CHECK: OUT([[OUTREG:r[0-9]+]]), IN([[OUTREG]])
+  %addr = alloca i64
+  call void asm "OUT($0), IN($1)", "=*rm,0"(i64* %addr, i64 %in)
+  ret i64 %in
+}