Fix SingleSource/Regression/C/2005-05-06-LongLongSignedShift.c, we were not

properly sign extending the top of the result of a 64-bit shift right by
a constant > 32.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21120 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelSimple.cpp b/lib/Target/X86/X86ISelSimple.cpp
index b39396854dd9d40ed7cafd1c679ec1f373cb5562..48546aa54f0083e8f15312f3defd243b00d44f10 100644 (file)
--- a/lib/Target/X86/X86ISelSimple.cpp
+++ b/lib/Target/X86/X86ISelSimple.cpp
@@ -3074,7 +3074,11 @@ void X86ISel::emitShiftOperation(MachineBasicBlock *MBB,
         } else {
           BuildMI(*MBB, IP, isSigned ? X86::SAR32ri : X86::SHR32ri, 2,
                   DestReg).addReg(SrcReg+1).addImm(Amount);
-          BuildMI(*MBB, IP, X86::MOV32ri, 1, DestReg+1).addImm(0);
+          if (isSigned)
+            BuildMI(*MBB, IP, X86::SAR32ri, 2,
+                    DestReg+1).addReg(SrcReg+1).addImm(31);
+          else
+            BuildMI(*MBB, IP, X86::MOV32ri, 1, DestReg+1).addImm(0);
         }
       }
     } else {