[llvm-commits] [llvm] r45620 - /llvm/trunk/lib/Target/X86/X86InstrInfo.cpp

Chris Lattner sabre at nondot.org
Fri Jan 4 21:19:56 PST 2008


Author: lattner
Date: Fri Jan  4 23:19:56 2008
New Revision: 45620

URL: http://llvm.org/viewvc/llvm-project?rev=45620&view=rev
Log:
factor some code better to avoid redundancy between 
isReallySideEffectFree and isReallyTriviallyReMaterializable.  Why is a load from
a global considered side-effect-free but not rematable?

Modified:
    llvm/trunk/lib/Target/X86/X86InstrInfo.cpp

Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.cpp?rev=45620&r1=45619&r2=45620&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.cpp Fri Jan  4 23:19:56 2008
@@ -135,11 +135,13 @@
   case X86::MMX_MOVD64rm:
   case X86::MMX_MOVQ64rm:
     // Loads from constant pools are trivially rematerializable.
-    return MI->getOperand(1).isRegister() && MI->getOperand(2).isImmediate() &&
-           MI->getOperand(3).isRegister() && MI->getOperand(4).isConstantPoolIndex() &&
-           MI->getOperand(1).getReg() == 0 &&
-           MI->getOperand(2).getImm() == 1 &&
-           MI->getOperand(3).getReg() == 0;
+    if (MI->getOperand(1).isReg() && MI->getOperand(2).isImm() &&
+        MI->getOperand(3).isReg() && MI->getOperand(4).isCPI() &&
+        MI->getOperand(1).getReg() == 0 &&
+        MI->getOperand(2).getImm() == 1 &&
+        MI->getOperand(3).getReg() == 0)
+      return true;
+    return false;
   }
   // All other instructions marked M_REMATERIALIZABLE are always trivially
   // rematerializable.
@@ -168,32 +170,11 @@
           MI->getOperand(3).getReg() == 0)
         return true;
     }
-    // FALLTHROUGH
-  case X86::MOV8rm:
-  case X86::MOV16rm:
-  case X86::MOV16_rm:
-  case X86::MOV32_rm:
-  case X86::MOV64rm:
-  case X86::LD_Fp64m:
-  case X86::MOVSSrm:
-  case X86::MOVSDrm:
-  case X86::MOVAPSrm:
-  case X86::MOVAPDrm:
-  case X86::MMX_MOVD64rm:
-  case X86::MMX_MOVQ64rm:
-    // Loads from constant pools have no side effects
-    return MI->getOperand(1).isRegister() &&
-           MI->getOperand(2).isImmediate() &&
-           MI->getOperand(3).isRegister() &&
-           MI->getOperand(4).isConstantPoolIndex() &&
-           MI->getOperand(1).getReg() == 0 &&
-           MI->getOperand(2).getImm() == 1 &&
-           MI->getOperand(3).getReg() == 0;
+    break;
   }
 
-  // All other instances of these instructions are presumed to have side
-  // effects.
-  return false;
+  // Anything that is rematerializable obviously has no side effects.
+  return isReallyTriviallyReMaterializable(MI);
 }
 
 /// hasLiveCondCodeDef - True if MI has a condition code def, e.g. EFLAGS, that





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