s390: improve floating point and integer convertion

src/s390/code-stubs-s390.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_S390
 
 #include "src/code-stubs.h"
 #include "src/api-arguments.h"
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 69 matching lines @@
 
   __ push(scratch);
   // Account for saved regs if input is sp.
   if (input_reg.is(sp)) double_offset += kPointerSize;
 
   if (!skip_fastpath()) {
     // Load double input.
     __ LoadDouble(double_scratch, MemOperand(input_reg, double_offset));
 
     // Do fast-path convert from double to int.
-    __ ConvertDoubleToInt64(double_scratch,
-#if !V8_TARGET_ARCH_S390X
-                            scratch,
-#endif
-                            result_reg, d0);
+    __ ConvertDoubleToInt64(result_reg, double_scratch);
 
-// Test for overflow
-#if V8_TARGET_ARCH_S390X
-    __ TestIfInt32(result_reg, r0);
-#else
-    __ TestIfInt32(scratch, result_reg, r0);
-#endif
+    // Test for overflow
+    __ TestIfInt32(result_reg);
     __ beq(&fastpath_done, Label::kNear);
   }
 
   __ Push(scratch_high, scratch_low);
   // Account for saved regs if input is sp.
   if (input_reg.is(sp)) double_offset += 2 * kPointerSize;
 
   __ LoadlW(scratch_high,
             MemOperand(input_reg, double_offset + Register::kExponentOffset));
   __ LoadlW(scratch_low,
@@ skipping 627 matching lines @@
 
   // Get two copies of exponent in the registers scratch and exponent.
   if (exponent_type() == INTEGER) {
     __ LoadRR(scratch, exponent);
   } else {
     // Exponent has previously been stored into scratch as untagged integer.
     __ LoadRR(exponent, scratch);
   }
   __ ldr(double_scratch, double_base);  // Back up base.
   __ LoadImmP(scratch2, Operand(1));
-  __ ConvertIntToDouble(scratch2, double_result);
+  __ ConvertIntToDouble(double_result, scratch2);
 
   // Get absolute value of exponent.
   Label positive_exponent;
   __ CmpP(scratch, Operand::Zero());
   __ bge(&positive_exponent, Label::kNear);
   __ LoadComplementRR(scratch, scratch);
   __ bind(&positive_exponent);
 
   Label while_true, no_carry, loop_end;
   __ bind(&while_true);
   __ mov(scratch2, Operand(1));
   __ AndP(scratch2, scratch);
   __ beq(&no_carry, Label::kNear);
   __ mdbr(double_result, double_scratch);
   __ bind(&no_carry);
   __ ShiftRightP(scratch, scratch, Operand(1));
   __ LoadAndTestP(scratch, scratch);
   __ beq(&loop_end, Label::kNear);
   __ mdbr(double_scratch, double_scratch);
   __ b(&while_true);
   __ bind(&loop_end);
 
   __ CmpP(exponent, Operand::Zero());
   __ bge(&done);
 
   // get 1/double_result:
   __ ldr(double_scratch, double_result);
   __ LoadImmP(scratch2, Operand(1));
-  __ ConvertIntToDouble(scratch2, double_result);
+  __ ConvertIntToDouble(double_result, scratch2);
   __ ddbr(double_result, double_scratch);
 
   // Test whether result is zero.  Bail out to check for subnormal result.
   // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
   __ lzdr(kDoubleRegZero);
   __ cdbr(double_result, kDoubleRegZero);
   __ bne(&done, Label::kNear);
   // double_exponent may not containe the exponent value if the input was a
   // smi.  We set it with exponent value before bailing out.
-  __ ConvertIntToDouble(exponent, double_exponent);
+  __ ConvertIntToDouble(double_exponent, exponent);
 
   // Returning or bailing out.
   __ push(r14);
   {
     AllowExternalCallThatCantCauseGC scope(masm);
     __ PrepareCallCFunction(0, 2, scratch);
     __ MovToFloatParameters(double_base, double_exponent);
     __ CallCFunction(
         ExternalReference::power_double_double_function(isolate()), 0, 2);
   }
@@ skipping 2324 matching lines @@
   CallApiFunctionAndReturn(masm, api_function_address, thunk_ref,
                            kStackUnwindSpace, NULL, return_value_operand, NULL);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_S390