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/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 87c6cf0..ad26719 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -151,6 +151,7 @@
SDOperand visitZERO_EXTEND(SDNode *N);
SDOperand visitSIGN_EXTEND_INREG(SDNode *N);
SDOperand visitTRUNCATE(SDNode *N);
+ SDOperand visitBIT_CONVERT(SDNode *N);
SDOperand visitFADD(SDNode *N);
SDOperand visitFSUB(SDNode *N);
@@ -609,6 +610,7 @@
case ISD::ZERO_EXTEND: return visitZERO_EXTEND(N);
case ISD::SIGN_EXTEND_INREG: return visitSIGN_EXTEND_INREG(N);
case ISD::TRUNCATE: return visitTRUNCATE(N);
+ case ISD::BIT_CONVERT: return visitBIT_CONVERT(N);
case ISD::FADD: return visitFADD(N);
case ISD::FSUB: return visitFSUB(N);
case ISD::FMUL: return visitFMUL(N);
@@ -1745,6 +1747,19 @@
return SDOperand();
}
+SDOperand DAGCombiner::visitBIT_CONVERT(SDNode *N) {
+ SDOperand N0 = N->getOperand(0);
+ MVT::ValueType VT = N->getValueType(0);
+
+ // If the input is a constant, let getNode() fold it.
+ if (isa<ConstantSDNode>(N0) || isa<ConstantFPSDNode>(N0)) {
+ SDOperand Res = DAG.getNode(ISD::BIT_CONVERT, VT, N0);
+ if (Res.Val != N) return Res;
+ }
+
+ return SDOperand();
+}
+
SDOperand DAGCombiner::visitFADD(SDNode *N) {
SDOperand N0 = N->getOperand(0);
SDOperand N1 = N->getOperand(1);