Fold promoted loads into binary ops for FP, allowing us to generate m32 forms

of FP ops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19834 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2005-01-25 20:03:11 +00:00
parent d279b4157a
commit 44129b5b68

View File

@ -371,7 +371,8 @@ namespace {
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
virtual void InstructionSelectBasicBlock(SelectionDAG &DAG);
bool isFoldableLoad(SDOperand Op, SDOperand OtherOp);
bool isFoldableLoad(SDOperand Op, SDOperand OtherOp,
bool FloatPromoteOk = false);
void EmitFoldedLoad(SDOperand Op, X86AddressMode &AM);
bool TryToFoldLoadOpStore(SDNode *Node);
@ -1119,11 +1120,19 @@ void ISel::EmitCMP(SDOperand LHS, SDOperand RHS, bool HasOneUse) {
/// isFoldableLoad - Return true if this is a load instruction that can safely
/// be folded into an operation that uses it.
bool ISel::isFoldableLoad(SDOperand Op, SDOperand OtherOp) {
if (Op.getOpcode() != ISD::LOAD ||
// FIXME: currently can't fold constant pool indexes.
isa<ConstantPoolSDNode>(Op.getOperand(1)))
bool ISel::isFoldableLoad(SDOperand Op, SDOperand OtherOp, bool FloatPromoteOk){
if (Op.getOpcode() == ISD::LOAD) {
// FIXME: currently can't fold constant pool indexes.
if (isa<ConstantPoolSDNode>(Op.getOperand(1)))
return false;
} else if (FloatPromoteOk && Op.getOpcode() == ISD::EXTLOAD &&
cast<MVTSDNode>(Op)->getExtraValueType() == MVT::f32) {
// FIXME: currently can't fold constant pool indexes.
if (isa<ConstantPoolSDNode>(Op.getOperand(1)))
return false;
} else {
return false;
}
// If this load has already been emitted, we clearly can't fold it.
assert(Op.ResNo == 0 && "Not a use of the value of the load?");
@ -1686,12 +1695,12 @@ unsigned ISel::SelectExpr(SDOperand N) {
Op0 = N.getOperand(0);
Op1 = N.getOperand(1);
if (isFoldableLoad(Op0, Op1)) {
if (isFoldableLoad(Op0, Op1, true)) {
std::swap(Op0, Op1);
goto FoldAdd;
}
if (isFoldableLoad(Op1, Op0)) {
if (isFoldableLoad(Op1, Op0, true)) {
FoldAdd:
switch (N.getValueType()) {
default: assert(0 && "Cannot add this type!");
@ -1699,8 +1708,10 @@ unsigned ISel::SelectExpr(SDOperand N) {
case MVT::i8: Opc = X86::ADD8rm; break;
case MVT::i16: Opc = X86::ADD16rm; break;
case MVT::i32: Opc = X86::ADD32rm; break;
case MVT::f32: Opc = X86::FADD32m; break;
case MVT::f64: Opc = X86::FADD64m; break;
case MVT::f64:
// For F64, handle promoted load operations (from F32) as well!
Opc = Op1.getOpcode() == ISD::LOAD ? X86::FADD64m : X86::FADD32m;
break;
}
X86AddressMode AM;
EmitFoldedLoad(Op1, AM);
@ -1893,18 +1904,18 @@ unsigned ISel::SelectExpr(SDOperand N) {
}
}
if (isFoldableLoad(Op0, Op1))
if (isFoldableLoad(Op0, Op1, true))
if (Node->getOpcode() != ISD::SUB) {
std::swap(Op0, Op1);
goto FoldOps;
} else {
// Emit 'reverse' subract, with a memory operand.
switch (N.getValueType()) {
default: Opc = 0; break;
case MVT::f32: Opc = X86::FSUBR32m; break;
case MVT::f64: Opc = X86::FSUBR64m; break;
}
if (Opc) {
// For FP, emit 'reverse' subract, with a memory operand.
if (N.getValueType() == MVT::f64) {
if (Op0.getOpcode() == ISD::EXTLOAD)
Opc = X86::FSUBR32m;
else
Opc = X86::FSUBR64m;
X86AddressMode AM;
EmitFoldedLoad(Op0, AM);
Tmp1 = SelectExpr(Op1);
@ -1913,7 +1924,7 @@ unsigned ISel::SelectExpr(SDOperand N) {
}
}
if (isFoldableLoad(Op1, Op0)) {
if (isFoldableLoad(Op1, Op0, true)) {
FoldOps:
switch (N.getValueType()) {
default: assert(0 && "Cannot operate on this type!");
@ -1921,8 +1932,8 @@ unsigned ISel::SelectExpr(SDOperand N) {
case MVT::i8: Opc = 5; break;
case MVT::i16: Opc = 6; break;
case MVT::i32: Opc = 7; break;
case MVT::f32: Opc = 8; break;
case MVT::f64: Opc = 9; break;
// For F64, handle promoted load operations (from F32) as well!
case MVT::f64: Opc = Op1.getOpcode() == ISD::LOAD ? 9 : 8; break;
}
switch (Node->getOpcode()) {
default: assert(0 && "Unreachable!");