S390: [builtins] Migrate Math.log to TurboFan.

Port f2da19fe

Original commit message:

    Introduce a dedicated Float64Log machine operator, that is either
    implemented by a direct C call or by platform specific code, i.e.
    using the FPU on x64 and ia32.

    This operator is used to implement Math.log as a proper TurboFan
    builtin on top of the CodeStubAssembler.

    Also introduce a NumberLog simplified operator on top of Float64Log
    and use that for the fast inline path of Math.log inside TurboFan
    optimized code.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com, bjaideep@ca.ibm.com
BUG=

Review-Url: https://codereview.chromium.org/2033353003
Cr-Commit-Position: refs/heads/master@{#36724}

src/compiler/s390/code-generator-s390.cc

@@ -1219,6 +1219,18 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
     case kS390_ModDouble:
       ASSEMBLE_FLOAT_MODULO();
       break;
+    case kS390_LogDouble: {
+      // TODO(bmeurer): We should really get rid of this special instruction,
+      // and generate a CallAddress instruction instead.
+      FrameScope scope(masm(), StackFrame::MANUAL);
+      __ PrepareCallCFunction(0, 1, kScratchReg);
+      __ MovToFloatParameter(i.InputDoubleRegister(0));
+      __ CallCFunction(ExternalReference::math_log_double_function(isolate()),
+                       0, 1);
+      // Move the result in the double result register.
+      __ MovFromFloatResult(i.OutputDoubleRegister());
+      break;
+    }
     case kS390_Neg:
       __ LoadComplementRR(i.OutputRegister(), i.InputRegister(0));
       break;

src/compiler/s390/instruction-codes-s390.h

@@ -61,6 +61,7 @@ namespace compiler {
   V(S390_ModU32)                   \
   V(S390_ModU64)                   \
   V(S390_ModDouble)                \
+  V(S390_LogDouble)                \
   V(S390_Neg)                      \
   V(S390_NegDouble)                \
   V(S390_SqrtFloat)                \

src/compiler/s390/instruction-scheduler-s390.cc

@@ -62,6 +62,7 @@ int InstructionScheduler::GetTargetInstructionFlags(
     case kS390_ModU32:
     case kS390_ModU64:
     case kS390_ModDouble:
+    case kS390_LogDouble:
     case kS390_Neg:
     case kS390_NegDouble:
     case kS390_SqrtFloat:

src/compiler/s390/instruction-selector-s390.cc

@@ -1191,6 +1191,13 @@ void InstructionSelector::VisitFloat64Abs(Node* node) {
   VisitRR(this, kS390_AbsDouble, node);
 }
 
+void InstructionSelector::VisitFloat64Log(Node* node) {
+  S390OperandGenerator g(this);
+  Emit(kS390_LogDouble, g.DefineAsFixed(node, d1),
+       g.UseFixed(node->InputAt(0), d1))
+      ->MarkAsCall();
+}
+
 void InstructionSelector::VisitFloat32Sqrt(Node* node) {
   VisitRR(this, kS390_SqrtFloat, node);
 }