[llvm-commits] [llvm] r60011 - /llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp
Chris Lattner
sabre at nondot.org
Mon Nov 24 21:15:49 PST 2008
Author: lattner
Date: Mon Nov 24 23:15:49 2008
New Revision: 60011
URL: http://llvm.org/viewvc/llvm-project?rev=60011&view=rev
Log:
refactor all the constantexpr/instruction handling code out into a
new FindMaximalLegalAddressingModeForOperation helper method.
Modified:
llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp
Modified: llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp?rev=60011&r1=60010&r2=60011&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp Mon Nov 24 23:15:49 2008
@@ -573,61 +573,22 @@
return true;
}
-
-/// FindMaximalLegalAddressingMode - If we can, try to merge the computation of
-/// Addr into the specified addressing mode. If Addr can't be added to AddrMode
-/// this returns false. This assumes that Addr is either a pointer type or
-/// intptr_t for the target.
-///
-/// This method is used to optimize both load/store and inline asms with memory
-/// operands.
static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
ExtAddrMode &AddrMode,
+ SmallVectorImpl<Instruction*> &AMI,
+ const TargetLowering &TLI,
+ unsigned Depth);
+
+/// FindMaximalLegalAddressingModeForOperation - Given an instruction or
+/// constant expr, see if we can fold the operation into the addressing mode.
+/// If so, update the addressing mode and return true, otherwise return false.
+static bool
+FindMaximalLegalAddressingModeForOperation(User *AddrInst, unsigned Opcode,
+ const Type *AccessTy,
+ ExtAddrMode &AddrMode,
SmallVectorImpl<Instruction*> &AddrModeInsts,
const TargetLowering &TLI,
unsigned Depth) {
-
- // If this is a global variable, fold it into the addressing mode if possible.
- if (GlobalValue *GV = dyn_cast<GlobalValue>(Addr)) {
- if (AddrMode.BaseGV == 0) {
- AddrMode.BaseGV = GV;
- if (TLI.isLegalAddressingMode(AddrMode, AccessTy))
- return true;
- AddrMode.BaseGV = 0;
- }
- } else if (ConstantInt *CI = dyn_cast<ConstantInt>(Addr)) {
- AddrMode.BaseOffs += CI->getSExtValue();
- if (TLI.isLegalAddressingMode(AddrMode, AccessTy))
- return true;
- AddrMode.BaseOffs -= CI->getSExtValue();
- } else if (isa<ConstantPointerNull>(Addr)) {
- return true;
- }
-
- // Look through constant exprs and instructions.
- unsigned Opcode = ~0U;
- User *AddrInst = 0;
- if (Instruction *I = dyn_cast<Instruction>(Addr)) {
- Opcode = I->getOpcode();
- AddrInst = I;
- } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Addr)) {
- Opcode = CE->getOpcode();
- AddrInst = CE;
- }
-
- // Limit recursion to avoid exponential behavior.
- if (Depth == 5) { AddrInst = 0; Opcode = ~0U; }
-
- // If this is really an instruction, add it to our list of related
- // instructions.
- if (Instruction *I = dyn_cast_or_null<Instruction>(AddrInst))
- AddrModeInsts.push_back(I);
-
-#if 0
- if (AddrInst && !AddrInst->hasOneUse())
- ;
- else
-#endif
switch (Opcode) {
case Instruction::PtrToInt:
// PtrToInt is always a noop, as we know that the int type is pointer sized.
@@ -653,18 +614,18 @@
FindMaximalLegalAddressingMode(AddrInst->getOperand(0), AccessTy,
AddrMode, AddrModeInsts, TLI, Depth+1))
return true;
-
+
// Restore the old addr mode info.
AddrMode = BackupAddrMode;
AddrModeInsts.resize(OldSize);
-
+
// Otherwise this was over-aggressive. Try merging in the LHS then the RHS.
if (FindMaximalLegalAddressingMode(AddrInst->getOperand(0), AccessTy,
AddrMode, AddrModeInsts, TLI, Depth+1) &&
FindMaximalLegalAddressingMode(AddrInst->getOperand(1), AccessTy,
AddrMode, AddrModeInsts, TLI, Depth+1))
return true;
-
+
// Otherwise we definitely can't merge the ADD in.
AddrMode = BackupAddrMode;
AddrModeInsts.resize(OldSize);
@@ -684,7 +645,7 @@
int64_t Scale = RHS->getSExtValue();
if (Opcode == Instruction::Shl)
Scale = 1 << Scale;
-
+
if (TryMatchingScaledValue(AddrInst->getOperand(0), Scale, AccessTy,
AddrMode, AddrModeInsts, TLI, Depth))
return true;
@@ -695,7 +656,7 @@
// one variable offset.
int VariableOperand = -1;
unsigned VariableScale = 0;
-
+
int64_t ConstantOffset = 0;
const TargetData *TD = TLI.getTargetData();
gep_type_iterator GTI = gep_type_begin(AddrInst);
@@ -703,7 +664,7 @@
if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
const StructLayout *SL = TD->getStructLayout(STy);
unsigned Idx =
- cast<ConstantInt>(AddrInst->getOperand(i))->getZExtValue();
+ cast<ConstantInt>(AddrInst->getOperand(i))->getZExtValue();
ConstantOffset += SL->getElementOffset(Idx);
} else {
uint64_t TypeSize = TD->getABITypeSize(GTI.getIndexedType());
@@ -715,18 +676,18 @@
VariableOperand = -2;
break;
}
-
+
// Remember the variable index.
VariableOperand = i;
VariableScale = TypeSize;
}
}
}
-
+
// If the GEP had multiple variable indices, punt.
if (VariableOperand == -2)
break;
-
+
// A common case is for the GEP to only do a constant offset. In this case,
// just add it to the disp field and check validity.
if (VariableOperand == -1) {
@@ -751,14 +712,14 @@
AddrMode.BaseReg = AddrInst->getOperand(0);
SetBaseReg = true;
}
-
+
// See if the scale amount is valid for this target.
AddrMode.BaseOffs += ConstantOffset;
if (TryMatchingScaledValue(AddrInst->getOperand(VariableOperand),
VariableScale, AccessTy, AddrMode,
AddrModeInsts, TLI, Depth)) {
if (!SetBaseReg) return true;
-
+
// If this match succeeded, we know that we can form an address with the
// GepBase as the basereg. See if we can match *more*.
AddrMode.HasBaseReg = false;
@@ -773,7 +734,7 @@
AddrMode.BaseReg = AddrInst->getOperand(0);
return true;
}
-
+
AddrMode.BaseOffs -= ConstantOffset;
if (SetBaseReg) {
AddrMode.HasBaseReg = false;
@@ -783,12 +744,54 @@
break;
}
}
+ return false;
+}
- if (Instruction *I = dyn_cast_or_null<Instruction>(AddrInst)) {
- assert(AddrModeInsts.back() == I && "Stack imbalance"); I = I;
- AddrModeInsts.pop_back();
+/// FindMaximalLegalAddressingMode - If we can, try to merge the computation of
+/// Addr into the specified addressing mode. If Addr can't be added to AddrMode
+/// this returns false. This assumes that Addr is either a pointer type or
+/// intptr_t for the target.
+///
+/// This method is used to optimize both load/store and inline asms with memory
+/// operands.
+static bool FindMaximalLegalAddressingMode(Value *Addr, const Type *AccessTy,
+ ExtAddrMode &AddrMode,
+ SmallVectorImpl<Instruction*> &AddrModeInsts,
+ const TargetLowering &TLI,
+ unsigned Depth) {
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(Addr)) {
+ // Fold in immediates if legal for the target.
+ AddrMode.BaseOffs += CI->getSExtValue();
+ if (TLI.isLegalAddressingMode(AddrMode, AccessTy))
+ return true;
+ AddrMode.BaseOffs -= CI->getSExtValue();
+ } else if (GlobalValue *GV = dyn_cast<GlobalValue>(Addr)) {
+ // If this is a global variable, fold it into the addressing mode if possible.
+ if (AddrMode.BaseGV == 0) {
+ AddrMode.BaseGV = GV;
+ if (TLI.isLegalAddressingMode(AddrMode, AccessTy))
+ return true;
+ AddrMode.BaseGV = 0;
+ }
+ } else if (Instruction *I = dyn_cast<Instruction>(Addr)) {
+ if (Depth < 5 && // Limit recursion to avoid exponential behavior.
+ FindMaximalLegalAddressingModeForOperation(I, I->getOpcode(),
+ AccessTy, AddrMode,
+ AddrModeInsts, TLI, Depth)) {
+ AddrModeInsts.push_back(I);
+ return true;
+ }
+ } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Addr)) {
+ if (Depth < 5 && // Limit recursion to avoid exponential behavior.
+ FindMaximalLegalAddressingModeForOperation(CE, CE->getOpcode(),
+ AccessTy, AddrMode,
+ AddrModeInsts, TLI, Depth))
+ return true;
+ } else if (isa<ConstantPointerNull>(Addr)) {
+ return true;
}
+
// Worse case, the target should support [reg] addressing modes. :)
if (!AddrMode.HasBaseReg) {
AddrMode.HasBaseReg = true;
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