[llvm-commits] [llvm] r152847 - /llvm/trunk/lib/Target/ARM/ARMFastISel.cpp

[Chad Rosier]

Author: mcrosier
Date: Thu Mar 15 16:40:23 2012
New Revision: 152847

URL: http://llvm.org/viewvc/llvm-project?rev=152847&view=rev
Log:
[fast-isel] Don't try to encode LONG_MIN using cmn instructions.
rdar://11038907

Modified:
    llvm/trunk/lib/Target/ARM/ARMFastISel.cpp

Modified: llvm/trunk/lib/Target/ARM/ARMFastISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMFastISel.cpp?rev=152847&r1=152846&r2=152847&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMFastISel.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMFastISel.cpp Thu Mar 15 16:40:23 2012
@@ -1384,12 +1384,16 @@
         SrcVT == MVT::i1) {
       const APInt &CIVal = ConstInt->getValue();
       Imm = (isZExt) ? (int)CIVal.getZExtValue() : (int)CIVal.getSExtValue();
-      if (Imm < 0) {
-        isNegativeImm = true;
-        Imm = -Imm;
+      // We can't encode LONG_MIN (i.e., 0x80000000) as an immediate because
+      // there is no way to represent 2147483648 as a signed 32-bit int.
+      if (Imm != (int)0x80000000) {
+        if (Imm < 0) {
+          isNegativeImm = true;
+          Imm = -Imm;
+        }
+        UseImm = isThumb2 ? (ARM_AM::getT2SOImmVal(Imm) != -1) :
+          (ARM_AM::getSOImmVal(Imm) != -1);
       }
-      UseImm = isThumb2 ? (ARM_AM::getT2SOImmVal(Imm) != -1) :
-        (ARM_AM::getSOImmVal(Imm) != -1);
     }
   } else if (const ConstantFP *ConstFP = dyn_cast<ConstantFP>(Src2Value)) {
     if (SrcVT == MVT::f32 || SrcVT == MVT::f64)