MIPS: ARM: Fast path for integer inputs to EmitVFPTruncate

src/mips/lithium-codegen-mips.cc

 // 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 3246 matching lines @@
     // If smi, handle it directly.
     EmitIntegerMathAbs(instr);
     __ bind(deferred->exit());
   }
 }
 
 
 void LCodeGen::DoMathFloor(LUnaryMathOperation* instr) {
   DoubleRegister input = ToDoubleRegister(instr->value());
   Register result = ToRegister(instr->result());
-  FPURegister single_scratch = double_scratch0().low();
   Register scratch1 = scratch0();
   Register except_flag = ToRegister(instr->temp());
 
   __ EmitFPUTruncate(kRoundToMinusInf,
-                     single_scratch,
+                     result,
                      input,
                      scratch1,
+                     double_scratch0(),
                      except_flag);
 
   // Deopt if the operation did not succeed.
   DeoptimizeIf(ne, instr->environment(), except_flag, Operand(zero_reg));
 
-  // Load the result.
-  __ mfc1(result, single_scratch);
-
   if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
     // Test for -0.
     Label done;
     __ Branch(&done, ne, result, Operand(zero_reg));
     __ mfc1(scratch1, input.high());
     __ And(scratch1, scratch1, Operand(HeapNumber::kSignMask));
     DeoptimizeIf(ne, instr->environment(), scratch1, Operand(zero_reg));
     __ bind(&done);
   }
 }
 
 
 void LCodeGen::DoMathRound(LUnaryMathOperation* instr) {
   DoubleRegister input = ToDoubleRegister(instr->value());
   Register result = ToRegister(instr->result());
+  DoubleRegister double_scratch1 = ToDoubleRegister(instr->temp());
   Register scratch = scratch0();
   Label done, check_sign_on_zero;
 
   // Extract exponent bits.
   __ mfc1(result, input.high());
   __ Ext(scratch,
          result,
          HeapNumber::kExponentShift,
          HeapNumber::kExponentBits);
 
@@ skipping 31 matching lines @@
     Label skip2;
     // ARM uses 'mi' here, which is 'lt'
     // Negating it results in 'ge'
     __ Branch(&skip2, ge, result, Operand(zero_reg));
     __ mov(result, zero_reg);
     __ Branch(&done);
     __ bind(&skip2);
   }
 
   Register except_flag = scratch;
-
   __ EmitFPUTruncate(kRoundToMinusInf,
-                     double_scratch0().low(),
+                     result,
                      double_scratch0(),
-                     result,
+                     at,
+                     double_scratch1,
                      except_flag);
 
   DeoptimizeIf(ne, instr->environment(), except_flag, Operand(zero_reg));
 
-  __ mfc1(result, double_scratch0().low());
-
   if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
     // Test for -0.
     __ Branch(&done, ne, result, Operand(zero_reg));
     __ bind(&check_sign_on_zero);
     __ mfc1(scratch, input.high());
     __ And(scratch, scratch, Operand(HeapNumber::kSignMask));
     DeoptimizeIf(ne, instr->environment(), scratch, Operand(zero_reg));
   }
   __ bind(&done);
 }
@@ skipping 1016 matching lines @@
   __ cvt_d_w(result_reg, result_reg);
   __ bind(&done);
 }
 
 
 void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
   Register input_reg = ToRegister(instr->value());
   Register scratch1 = scratch0();
   Register scratch2 = ToRegister(instr->temp());
   DoubleRegister double_scratch = double_scratch0();
-  FPURegister single_scratch = double_scratch.low();
+  DoubleRegister double_scratch2 = ToDoubleRegister(instr->temp3());
 
   ASSERT(!scratch1.is(input_reg) && !scratch1.is(scratch2));
   ASSERT(!scratch2.is(input_reg) && !scratch2.is(scratch1));
 
   Label done;
 
   // The input is a tagged HeapObject.
   // Heap number map check.
   __ lw(scratch1, FieldMemOperand(input_reg, HeapObject::kMapOffset));
   __ LoadRoot(at, Heap::kHeapNumberMapRootIndex);
   // This 'at' value and scratch1 map value are used for tests in both clauses
   // of the if.
 
   if (instr->truncating()) {
     Register scratch3 = ToRegister(instr->temp2());
-    DoubleRegister double_scratch2 = ToDoubleRegister(instr->temp3());
+    FPURegister single_scratch = double_scratch.low();
     ASSERT(!scratch3.is(input_reg) &&
            !scratch3.is(scratch1) &&
            !scratch3.is(scratch2));
     // Performs a truncating conversion of a floating point number as used by
     // the JS bitwise operations.
     Label heap_number;
     __ Branch(&heap_number, eq, scratch1, Operand(at));  // HeapNumber map?
     // Check for undefined. Undefined is converted to zero for truncating
     // conversions.
     __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
@@ skipping 14 matching lines @@
   } else {
     // Deoptimize if we don't have a heap number.
     DeoptimizeIf(ne, instr->environment(), scratch1, Operand(at));
 
     // Load the double value.
     __ ldc1(double_scratch,
             FieldMemOperand(input_reg, HeapNumber::kValueOffset));
 
     Register except_flag = scratch2;
     __ EmitFPUTruncate(kRoundToZero,
-                       single_scratch,
+                       input_reg,
                        double_scratch,
                        scratch1,
+                       double_scratch2,
                        except_flag,
                        kCheckForInexactConversion);
 
     // Deopt if the operation did not succeed.
     DeoptimizeIf(ne, instr->environment(), except_flag, Operand(zero_reg));
 
-    // Load the result.
-    __ mfc1(input_reg, single_scratch);
-
     if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
       __ Branch(&done, ne, input_reg, Operand(zero_reg));
 
       __ mfc1(scratch1, double_scratch.high());
       __ And(scratch1, scratch1, Operand(HeapNumber::kSignMask));
       DeoptimizeIf(ne, instr->environment(), scratch1, Operand(zero_reg));
     }
   }
   __ bind(&done);
 }
@@ skipping 41 matching lines @@
                    instr->hydrogen()->deoptimize_on_minus_zero(),
                    instr->environment());
 }
 
 
 void LCodeGen::DoDoubleToI(LDoubleToI* instr) {
   Register result_reg = ToRegister(instr->result());
   Register scratch1 = scratch0();
   Register scratch2 = ToRegister(instr->temp());
   DoubleRegister double_input = ToDoubleRegister(instr->value());
-  FPURegister single_scratch = double_scratch0().low();
 
   if (instr->truncating()) {
     Register scratch3 = ToRegister(instr->temp2());
+    FPURegister single_scratch = double_scratch0().low();
     __ EmitECMATruncate(result_reg,
                         double_input,
                         single_scratch,
                         scratch1,
                         scratch2,
                         scratch3);
   } else {
     Register except_flag = scratch2;
 
     __ EmitFPUTruncate(kRoundToMinusInf,
-                       single_scratch,
+                       result_reg,
                        double_input,
                        scratch1,
+                       double_scratch0(),
                        except_flag,
                        kCheckForInexactConversion);
 
     // Deopt if the operation did not succeed (except_flag != 0).
     DeoptimizeIf(ne, instr->environment(), except_flag, Operand(zero_reg));
-
-    // Load the result.
-    __ mfc1(result_reg, single_scratch);
   }
 }
 
 
 void LCodeGen::DoCheckSmi(LCheckSmi* instr) {
   LOperand* input = instr->value();
   __ And(at, ToRegister(input), Operand(kSmiTagMask));
   DeoptimizeIf(ne, instr->environment(), at, Operand(zero_reg));
 }
 
@@ skipping 946 matching lines @@
   __ Subu(scratch, result, scratch);
   __ lw(result, FieldMemOperand(scratch,
                                 FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal