constant fold bits_convert in getNode and in the dag combiner for fp<->int
conversions. This allows V8 to compiles this:
void %test() {
call float %test2( float 1.000000e+00, float 2.000000e+00, double 3.000000e+00, double* null )
ret void
}
into:
test:
save -96, %o6, %o6
sethi 0, %o3
sethi 1049088, %o2
sethi 1048576, %o1
sethi 1040384, %o0
or %g0, %o3, %o4
call test2
nop
restore %g0, %g0, %g0
retl
nop
instead of:
test:
save -112, %o6, %o6
sethi 0, %o4
sethi 1049088, %l0
st %o4, [%i6+-12]
st %l0, [%i6+-16]
ld [%i6+-12], %o3
ld [%i6+-16], %o2
sethi 1048576, %o1
sethi 1040384, %o0
call test2
nop
restore %g0, %g0, %g0
retl
nop
llvm-svn: 24980
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index ec75dfe..76d983f 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -828,6 +828,7 @@
SDOperand SelectionDAG::getNode(unsigned Opcode, MVT::ValueType VT,
SDOperand Operand) {
+ // Constant fold unary operations with an integer constant operand.
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Operand.Val)) {
uint64_t Val = C->getValue();
switch (Opcode) {
@@ -838,13 +839,25 @@
case ISD::TRUNCATE: return getConstant(Val, VT);
case ISD::SINT_TO_FP: return getConstantFP(C->getSignExtended(), VT);
case ISD::UINT_TO_FP: return getConstantFP(C->getValue(), VT);
+ case ISD::BIT_CONVERT:
+ if (VT == MVT::f32) {
+ assert(C->getValueType(0) == MVT::i32 && "Invalid bit_convert!");
+ return getConstantFP(BitsToFloat(Val), VT);
+ } else if (VT == MVT::f64) {
+ assert(C->getValueType(0) == MVT::i64 && "Invalid bit_convert!");
+ return getConstantFP(BitsToDouble(Val), VT);
+ }
+ break;
}
}
+ // Constant fold unary operations with an floating point constant operand.
if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Operand.Val))
switch (Opcode) {
case ISD::FNEG:
return getConstantFP(-C->getValue(), VT);
+ case ISD::FABS:
+ return getConstantFP(fabs(C->getValue()), VT);
case ISD::FP_ROUND:
case ISD::FP_EXTEND:
return getConstantFP(C->getValue(), VT);
@@ -852,6 +865,15 @@
return getConstant((int64_t)C->getValue(), VT);
case ISD::FP_TO_UINT:
return getConstant((uint64_t)C->getValue(), VT);
+ case ISD::BIT_CONVERT:
+ if (VT == MVT::i32) {
+ assert(C->getValueType(0) == MVT::f32 && "Invalid bit_convert!");
+ return getConstant(FloatToBits(C->getValue()), VT);
+ } else if (VT == MVT::i64) {
+ assert(C->getValueType(0) == MVT::f64 && "Invalid bit_convert!");
+ return getConstant(DoubleToBits(C->getValue()), VT);
+ }
+ break;
}
unsigned OpOpcode = Operand.Val->getOpcode();