Introduce InvokeMathCFunction that can be used to directly invoke mathematical function provided by…

runtime/vm/intermediate_language_ia32.cc

Index: runtime/vm/intermediate_language_ia32.cc
diff --git a/runtime/vm/intermediate_language_ia32.cc b/runtime/vm/intermediate_language_ia32.cc
index c336720b8ce7e18fce225630dd80b9c7cd768641..6dda843b95d67e83cc8cda104b11aede9395171e 100644
--- a/runtime/vm/intermediate_language_ia32.cc
+++ b/runtime/vm/intermediate_language_ia32.cc
@@ -2426,6 +2426,33 @@ void DoubleToDoubleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
 }
 
 
+LocationSummary* InvokeMathCFunctionInstr::MakeLocationSummary() const {
+  ASSERT((InputCount() == 1) || (InputCount() == 2));
+  const intptr_t kNumTemps = 0;
+  LocationSummary* result =
+      new LocationSummary(InputCount(), kNumTemps, LocationSummary::kCall);
+  result->set_in(0, Location::FpuRegisterLocation(XMM1, Location::kDouble));

[Florian Schneider, 2013/01/21 16:31:26]

Do you really need fixed locations here? You could also assign locations in a
loop from 0..InputCount()

[Vyacheslav Egorov (Google), 2013/01/21 16:50:08]

Instruction is marked as a call to ensure that register allocator takes care of
spilling.

+  if (InputCount() == 2) {
+    result->set_in(1, Location::FpuRegisterLocation(XMM2, Location::kDouble));
+  }
+  result->set_out(Location::FpuRegisterLocation(XMM1, Location::kDouble));
+  return result;
+}
+
+
+void InvokeMathCFunctionInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  __ enter(Immediate(0));
+  __ ReserveAlignedFrameSpace(kDoubleSize * InputCount());
+  for (intptr_t i = 0; i < InputCount(); i++) {
+    __ movsd(Address(ESP, -kDoubleSize * i), locs()->in(i).fpu_reg());
+  }
+  __ CallRuntime(TargetFunction());
+  __ fstpl(Address(ESP, 0));
+  __ movsd(locs()->out().fpu_reg(), Address(ESP, 0));
+  __ leave();
+}
+
+
 LocationSummary* PolymorphicInstanceCallInstr::MakeLocationSummary() const {
   return MakeCallSummary();
 }