[llvm-commits] [llvm] r83696 - in /llvm/trunk: include/llvm/Target/TargetInstrInfo.h lib/Target/X86/X86InstrInfo.cpp lib/Target/X86/X86InstrInfo.h

[Dan Gohman]

Author: djg
Date: Fri Oct  9 19:34:18 2009
New Revision: 83696

URL: http://llvm.org/viewvc/llvm-project?rev=83696&view=rev
Log:
Replace X86's CanRematLoadWithDispOperand by calling the target-independent
MachineInstr::isInvariantLoad instead, which has the benefit of being
more complete.

Modified:
    llvm/trunk/include/llvm/Target/TargetInstrInfo.h
    llvm/trunk/lib/Target/X86/X86InstrInfo.cpp
    llvm/trunk/lib/Target/X86/X86InstrInfo.h

Modified: llvm/trunk/include/llvm/Target/TargetInstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetInstrInfo.h?rev=83696&r1=83695&r2=83696&view=diff

==============================================================================
--- llvm/trunk/include/llvm/Target/TargetInstrInfo.h (original)
+++ llvm/trunk/include/llvm/Target/TargetInstrInfo.h Fri Oct  9 19:34:18 2009
@@ -107,7 +107,7 @@
                                    AliasAnalysis *AA = 0) const {
     return MI->getOpcode() == IMPLICIT_DEF ||
            (MI->getDesc().isRematerializable() &&
-            (isReallyTriviallyReMaterializable(MI) ||
+            (isReallyTriviallyReMaterializable(MI, AA) ||
              isReallyTriviallyReMaterializableGeneric(MI, AA)));
   }
 
@@ -118,7 +118,8 @@
   /// taking into consideration its operands. This predicate must return false
   /// if the instruction has any side effects other than producing a value, or
   /// if it requres any address registers that are not always available.
-  virtual bool isReallyTriviallyReMaterializable(const MachineInstr *MI) const {
+  virtual bool isReallyTriviallyReMaterializable(const MachineInstr *MI,
+                                                 AliasAnalysis *AA) const {
     return false;
   }
 

Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.cpp?rev=83696&r1=83695&r2=83696&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.cpp Fri Oct  9 19:34:18 2009
@@ -782,31 +782,9 @@
   return isPICBase;
 }
 
-/// CanRematLoadWithDispOperand - Return true if a load with the specified
-/// operand is a candidate for remat: for this to be true we need to know that
-/// the load will always return the same value, even if moved.
-static bool CanRematLoadWithDispOperand(const MachineOperand &MO,
-                                        X86TargetMachine &TM) {
-  // Loads from constant pool entries can be remat'd.
-  if (MO.isCPI()) return true;
-  
-  // We can remat globals in some cases.
-  if (MO.isGlobal()) {
-    // If this is a load of a stub, not of the global, we can remat it.  This
-    // access will always return the address of the global.
-    if (isGlobalStubReference(MO.getTargetFlags()))
-      return true;
-    
-    // If the global itself is constant, we can remat the load.
-    if (GlobalVariable *GV = dyn_cast<GlobalVariable>(MO.getGlobal()))
-      if (GV->isConstant())
-        return true;
-  }
-  return false;
-}
- 
 bool
-X86InstrInfo::isReallyTriviallyReMaterializable(const MachineInstr *MI) const {
+X86InstrInfo::isReallyTriviallyReMaterializable(const MachineInstr *MI,
+                                                AliasAnalysis *AA) const {
   switch (MI->getOpcode()) {
   default: break;
     case X86::MOV8rm:
@@ -825,7 +803,7 @@
       if (MI->getOperand(1).isReg() &&
           MI->getOperand(2).isImm() &&
           MI->getOperand(3).isReg() && MI->getOperand(3).getReg() == 0 &&
-          CanRematLoadWithDispOperand(MI->getOperand(4), TM)) {
+          MI->isInvariantLoad(AA)) {
         unsigned BaseReg = MI->getOperand(1).getReg();
         if (BaseReg == 0 || BaseReg == X86::RIP)
           return true;

Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.h?rev=83696&r1=83695&r2=83696&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.h (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.h Fri Oct  9 19:34:18 2009
@@ -451,7 +451,8 @@
   unsigned isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const;
   unsigned isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const;
 
-  bool isReallyTriviallyReMaterializable(const MachineInstr *MI) const;
+  bool isReallyTriviallyReMaterializable(const MachineInstr *MI,
+                                         AliasAnalysis *AA) const;
   void reMaterialize(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,
                      unsigned DestReg, unsigned SubIdx,
                      const MachineInstr *Orig) const;