Arrange to print constants that match "n" and "i" constraints

in inline asm as signed (what gcc does).  Add partial support
for x86-specific "e" and "Z" constraints, with appropriate
signedness for printing.

llvm-svn: 64400

1 files changed, 5 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index fce57f93b7f..909789b970b 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -2082,8 +2082,11 @@ void TargetLowering::LowerAsmOperandForConstraint(SDValue Op,
     if (C) {   // just C, no GV.
       // Simple constants are not allowed for 's'.
       if (ConstraintLetter != 's') {
-        Ops.push_back(DAG.getTargetConstant(C->getAPIntValue(),
-                                            Op.getValueType()));
+        // gcc prints these as sign extended.  Sign extend value to 64 bits
+        // now; without this it would get ZExt'd later in
+        // ScheduleDAGSDNodes::EmitNode, which is very generic.
+        Ops.push_back(DAG.getTargetConstant(C->getAPIntValue().getSExtValue(),
+                                            MVT::i64));
         return;
       }
     }