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

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

Index: src/compiler/s390/code-generator-s390.cc
diff --git a/src/compiler/s390/code-generator-s390.cc b/src/compiler/s390/code-generator-s390.cc
index 2c870af71e863304979070ee680855d2c7da4c2d..66fe6b72723b0302fb2465ad60ffca70df7a5d63 100644
--- a/src/compiler/s390/code-generator-s390.cc
+++ b/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;