Constant fold SIGN_EXTEND_INREG with ashr not lshr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47992 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index dd13435..0dba4a4 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -2029,7 +2029,7 @@
APInt Val = N1C->getAPIntValue();
unsigned FromBits = MVT::getSizeInBits(cast<VTSDNode>(N2)->getVT());
Val <<= Val.getBitWidth()-FromBits;
- Val = Val.lshr(Val.getBitWidth()-FromBits);
+ Val = Val.ashr(Val.getBitWidth()-FromBits);
return getConstant(Val, VT);
}
break;
diff --git a/test/CodeGen/ARM/2008-03-05-SxtInRegBug.ll b/test/CodeGen/ARM/2008-03-05-SxtInRegBug.ll
new file mode 100644
index 0000000..ca34275
--- /dev/null
+++ b/test/CodeGen/ARM/2008-03-05-SxtInRegBug.ll
@@ -0,0 +1,14 @@
+; RUN: llvm-as < %s | llc -march=arm -mattr=+v6 | not grep 255
+
+define i32 @main(i32 %argc, i8** %argv) {
+entry:
+ br label %bb1
+bb1: ; preds = %entry
+ %tmp3.i.i = load i8* null, align 1 ; <i8> [#uses=1]
+ %tmp4.i.i = icmp slt i8 %tmp3.i.i, 0 ; <i1> [#uses=1]
+ br i1 %tmp4.i.i, label %bb2, label %bb3
+bb2: ; preds = %bb1
+ ret i32 1
+bb3: ; preds = %bb1
+ ret i32 0
+}