[llvm-commits] CVS: llvm/lib/Transforms/Scalar/InstructionCombining.cpp

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.399 -> 1.400
---
Log message:

Remove a special case, allowing the general case to handle it.  No functionality
change.


---
Diffs of the changes:  (+37 -49)

 InstructionCombining.cpp |   86 ++++++++++++++++++++---------------------------
 1 files changed, 37 insertions(+), 49 deletions(-)


Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.399 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.400
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.399	Fri Oct 28 11:27:35 2005
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Fri Oct 28 22:19:53 2005
@@ -3814,59 +3814,47 @@
   uint64_t CastElTySize = TD->getTypeSize(CastElTy);
   if (CastElTySize == 0 || AllocElTySize == 0) return 0;
 
-  // If the allocation is for an even multiple of the cast type size
+  // See if we can satisfy the modulus by pulling a scale out of the array
+  // size argument.
+  unsigned ArraySizeScale = 1;
+  Value *NumElements = AI.getOperand(0);
+  
+  if (ConstantUInt *CI = dyn_cast<ConstantUInt>(NumElements)) {
+    ArraySizeScale = CI->getValue();
+    NumElements = ConstantUInt::get(Type::UIntTy, 1);
+  } else if (ShiftInst *SI = dyn_cast<ShiftInst>(NumElements)) {
+    if (SI->getOpcode() == Instruction::Shl)
+      if (ConstantUInt *CUI = dyn_cast<ConstantUInt>(SI->getOperand(1))) {
+        // This is a value scaled by '1 << the shift amt'.
+        NumElements = SI->getOperand(0);
+        ArraySizeScale = 1U << CUI->getValue();
+      }
+  } else if (isa<Instruction>(NumElements) &&
+             cast<Instruction>(NumElements)->getOpcode() == Instruction::Mul){
+    BinaryOperator *BO = cast<BinaryOperator>(NumElements);
+    if (ConstantUInt *Scale = dyn_cast<ConstantUInt>(BO->getOperand(1))) {
+      // This value is scaled by 'Scale'.
+      NumElements = BO->getOperand(0);
+      ArraySizeScale = Scale->getValue();
+    }
+  }
+  
+  // If we can now satisfy the modulus, by using a non-1 scale, we really can
+  // do the xform.
+  if ((AllocElTySize*ArraySizeScale) % CastElTySize != 0) return 0;
+
+  unsigned Scale = (AllocElTySize*ArraySizeScale)/CastElTySize;
   Value *Amt = 0;
-  if (AllocElTySize % CastElTySize == 0) {
-    Amt = ConstantUInt::get(Type::UIntTy, AllocElTySize/CastElTySize);
-    if (ConstantUInt *CI = dyn_cast<ConstantUInt>(AI.getOperand(0)))
+  if (Scale == 1) {
+    Amt = NumElements;
+  } else {
+    Amt = ConstantUInt::get(Type::UIntTy, Scale);
+    if (ConstantUInt *CI = dyn_cast<ConstantUInt>(NumElements))
       Amt = ConstantExpr::getMul(CI, cast<ConstantUInt>(Amt));
-    else {
-      // Perform an explicit scale.
-      Instruction *Tmp = BinaryOperator::createMul(Amt, AI.getOperand(0),"tmp");
+    else if (Scale != 1) {
+      Instruction *Tmp = BinaryOperator::createMul(Amt, NumElements, "tmp");
       Amt = InsertNewInstBefore(Tmp, AI);
     }
-  } else {
-    // See if we can satisfy the modulus by pulling a scale out of the array
-    // size argument.
-    unsigned ArraySizeScale = 1;
-    Value *NumElements = AI.getOperand(0);
-    
-    if (ConstantUInt *CI = dyn_cast<ConstantUInt>(NumElements)) {
-      ArraySizeScale = CI->getValue();
-      NumElements = ConstantUInt::get(Type::UIntTy, 1);
-    } else if (ShiftInst *SI = dyn_cast<ShiftInst>(NumElements)) {
-      if (SI->getOpcode() == Instruction::Shl)
-        if (ConstantUInt *CUI = dyn_cast<ConstantUInt>(SI->getOperand(1))) {
-          // This is a value scaled by '1 << the shift amt'.
-          NumElements = SI->getOperand(0);
-          ArraySizeScale = 1U << CUI->getValue();
-        }
-    } else if (isa<Instruction>(NumElements) &&
-               cast<Instruction>(NumElements)->getOpcode() == Instruction::Mul){
-      BinaryOperator *BO = cast<BinaryOperator>(NumElements);
-      if (ConstantUInt *Scale = dyn_cast<ConstantUInt>(BO->getOperand(1))) {
-        // This value is scaled by 'Scale'.
-        NumElements = BO->getOperand(0);
-        ArraySizeScale = Scale->getValue();
-      }
-    }
-    
-    // If we can now satisfy the modulus, by using a non-1 scale, we really can
-    // do the xform.
-    if ((AllocElTySize*ArraySizeScale) % CastElTySize != 0) return 0;
-
-    unsigned Scale = (AllocElTySize*ArraySizeScale)/CastElTySize;
-    if (Scale == 1) {
-      Amt = NumElements;
-    } else {
-      Amt = ConstantUInt::get(Type::UIntTy, Scale);
-      if (ConstantUInt *CI = dyn_cast<ConstantUInt>(NumElements))
-        Amt = ConstantExpr::getMul(CI, cast<ConstantUInt>(Amt));
-      else if (Scale != 1) {
-        Instruction *Tmp = BinaryOperator::createMul(Amt, NumElements, "tmp");
-        Amt = InsertNewInstBefore(Tmp, AI);
-      }
-    }
   }
   
   std::string Name = AI.getName(); AI.setName("");