[llvm-commits] [llvm] r162520 - in /llvm/trunk/lib/Target/ARM: ARMInstrInfo.td MCTargetDesc/ARMMCCodeEmitter.cpp

[Richard Smith]

Author: rsmith
Date: Thu Aug 23 19:35:46 2012
New Revision: 162520

URL: http://llvm.org/viewvc/llvm-project?rev=162520&view=rev
Log:
Fix undefined behavior (negation of INT_MIN) in ARM backend.

Modified:
    llvm/trunk/lib/Target/ARM/ARMInstrInfo.td
    llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp

Modified: llvm/trunk/lib/Target/ARM/ARMInstrInfo.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMInstrInfo.td?rev=162520&r1=162519&r2=162520&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMInstrInfo.td (original)
+++ llvm/trunk/lib/Target/ARM/ARMInstrInfo.td Thu Aug 23 19:35:46 2012
@@ -275,7 +275,7 @@
 
 def so_imm_neg_asmoperand : AsmOperandClass { let Name = "ARMSOImmNeg"; }
 def so_imm_neg : Operand<i32>, PatLeaf<(imm), [{
-    int64_t Value = -(int)N->getZExtValue();
+    unsigned Value = -(unsigned)N->getZExtValue();
     return Value && ARM_AM::getSOImmVal(Value) != -1;
   }], imm_neg_XFORM> {
   let ParserMatchClass = so_imm_neg_asmoperand;

Modified: llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp?rev=162520&r1=162519&r2=162520&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp (original)
+++ llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp Thu Aug 23 19:35:46 2012
@@ -783,7 +783,7 @@
 
   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
   if (Imm8 < 0)
-    Imm8 = -Imm8;
+    Imm8 = -(uint32_t)Imm8;
 
   // Scaled by 4.
   Imm8 /= 4;