[v8-dev] Split and replace the EmitVFPTruncate routine to only do what is needed. Floor

src/arm/macro-assembler-arm.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 921 matching lines @@
   // dest. If the HeapNumber does not fit into a 32bits signed integer branch
   // to not_int32 label. If VFP3 is available double_scratch is used but not
   // scratch2.
   void ConvertToInt32(Register source,
                       Register dest,
                       Register scratch,
                       Register scratch2,
                       DwVfpRegister double_scratch,
                       Label *not_int32);
 
-  // Try to convert a double to a signed 32-bit integer. If the double value
-  // can be exactly represented as an integer, the code jumps to 'done' and
-  // 'result' contains the integer value. Otherwise, the code falls through.
-  void TryFastDoubleToInt32(Register result,
-                            DwVfpRegister double_input,
-                            DwVfpRegister double_scratch,
-                            Label* done);
+  // Check if a double can be exactly represented as a signed 32-bit integer.
+  // Z flag set to one if true.
+  void TestDoubleIsInt32(DwVfpRegister double_input,
+                         DwVfpRegister double_scratch);
 
-  // Truncates a double using a specific rounding mode, and writes the value
-  // to the result register.
-  // Clears the z flag (ne condition) if an overflow occurs.
-  // If kCheckForInexactConversion is passed, the z flag is also cleared if the
-  // conversion was inexact, i.e. if the double value could not be converted
-  // exactly to a 32-bit integer.
-  void EmitVFPTruncate(VFPRoundingMode rounding_mode,
-                       Register result,
-                       DwVfpRegister double_input,
-                       Register scratch,
-                       DwVfpRegister double_scratch,
-                       CheckForInexactConversion check
-                           = kDontCheckForInexactConversion);
+  // Try to convert a double to a signed 32-bit integer.
+  // Z flag set to one and result assigned if the conversion is exact.
+  void TryDoubleToInt32Exact(Register result,
+                             DwVfpRegister double_input,
+                             DwVfpRegister double_scratch);
+
+  // Floor a double and writes the value to the result register.
+  // Go to exact if the conversion is exact (to be able to test -0),
+  // fall through calling code if an overflow occurred, else go to done.
+  void TryInt32Floor(Register result,
+                     DwVfpRegister double_input,
+                     Register input_high,
+                     DwVfpRegister double_scratch,
+                     Label* done,
+                     Label* exact);
 
   // Helper for EmitECMATruncate.
   // This will truncate a floating-point value outside of the signed 32bit
   // integer range to a 32bit signed integer.
   // Expects the double value loaded in input_high and input_low.
   // Exits with the answer in 'result'.
   // Note that this code does not work for values in the 32bit range!
   void EmitOutOfInt32RangeTruncate(Register result,
                                    Register input_high,
                                    Register input_low,
@@ skipping 451 matching lines @@
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM_MACRO_ASSEMBLER_ARM_H_