Bug 1272939 - IonMonkey: MIPS: Refactor MacroAssembler::convertFloat32/DoubleToInt32. r=arai

---
 js/src/jit/mips32/MacroAssembler-mips32.cpp | 34 ++++++++++-------------------
 js/src/jit/mips64/MacroAssembler-mips64.cpp | 33 ++++++++++------------------
 2 files changed, 23 insertions(+), 44 deletions(-)

js/src/jit/mips32/MacroAssembler-mips32.cpp

@@ -120,23 +120,19 @@ void
 MacroAssemblerMIPSCompat::convertDoubleToInt32(FloatRegister src, Register dest,
                                          Label* fail, bool negativeZeroCheck)
 {
+    if (negativeZeroCheck) {
+        moveFromDoubleHi(src, dest);
+        moveFromDoubleLo(src, ScratchRegister);
+        as_movn(dest, zero, ScratchRegister);
+        ma_b(dest, Imm32(INT32_MIN), fail, Assembler::Equal);
+    }
+
     // Convert double to int, then convert back and check if we have the
     // same number.
     as_cvtwd(ScratchDoubleReg, src);
     as_mfc1(dest, ScratchDoubleReg);
     as_cvtdw(ScratchDoubleReg, ScratchDoubleReg);
     ma_bc1d(src, ScratchDoubleReg, fail, Assembler::DoubleNotEqualOrUnordered);
-
-    if (negativeZeroCheck) {
-        Label notZero;
-        ma_b(dest, Imm32(0), &notZero, Assembler::NotEqual, ShortJump);
-        // Test and bail for -0.0, when integer result is 0
-        // Move the top word of the double into the output reg, if it is
-        // non-zero, then the original value was -0.0
-        moveFromDoubleHi(src, dest);
-        ma_b(dest, Imm32(INT32_MIN), fail, Assembler::Equal);
-        bind(&notZero);
-    }
 }
 
 // Checks whether a float32 is representable as a 32-bit integer. If so, the
@@ -146,6 +142,11 @@ void
 MacroAssemblerMIPSCompat::convertFloat32ToInt32(FloatRegister src, Register dest,
                                           Label* fail, bool negativeZeroCheck)
 {
+    if (negativeZeroCheck) {
+        moveFromFloat32(src, dest);
+        ma_b(dest, Imm32(INT32_MIN), fail, Assembler::Equal);
+    }
+
     // Converting the floating point value to an integer and then converting it
     // back to a float32 would not work, as float to int32 conversions are
     // clamping (e.g. float(INT32_MAX + 1) would get converted into INT32_MAX
@@ -158,17 +159,6 @@ MacroAssemblerMIPSCompat::convertFloat32ToInt32(FloatRegister src, Register dest
 
     // Bail out in the clamped cases.
     ma_b(dest, Imm32(INT32_MAX), fail, Assembler::Equal);
-
-    if (negativeZeroCheck) {
-        Label notZero;
-        ma_b(dest, Imm32(0), &notZero, Assembler::NotEqual, ShortJump);
-        // Test and bail for -0.0, when integer result is 0
-        // Move the top word of the double into the output reg,
-        // if it is non-zero, then the original value was -0.0
-        moveFromDoubleHi(src, dest);
-        ma_b(dest, Imm32(INT32_MIN), fail, Assembler::Equal);
-        bind(&notZero);
-    }
 }
 
 void

js/src/jit/mips64/MacroAssembler-mips64.cpp

@@ -129,23 +129,18 @@ void
 MacroAssemblerMIPS64Compat::convertDoubleToInt32(FloatRegister src, Register dest,
                                                  Label* fail, bool negativeZeroCheck)
 {
+    if (negativeZeroCheck) {
+        moveFromDouble(src, dest);
+        ma_drol(dest, dest, Imm32(1));
+        ma_b(dest, Imm32(1), fail, Assembler::Equal);
+    }
+
     // Convert double to int, then convert back and check if we have the
     // same number.
     as_cvtwd(ScratchDoubleReg, src);
     as_mfc1(dest, ScratchDoubleReg);
     as_cvtdw(ScratchDoubleReg, ScratchDoubleReg);
     ma_bc1d(src, ScratchDoubleReg, fail, Assembler::DoubleNotEqualOrUnordered);
-
-    if (negativeZeroCheck) {
-        Label notZero;
-        ma_b(dest, Imm32(0), &notZero, Assembler::NotEqual, ShortJump);
-        // Test and bail for -0.0, when integer result is 0
-        // Move the top word of the double into the output reg, if it is
-        // non-zero, then the original value was -0.0
-        moveFromDoubleHi(src, dest);
-        ma_b(dest, Imm32(INT32_MIN), fail, Assembler::Equal);
-        bind(&notZero);
-    }
 }
 
 // Checks whether a float32 is representable as a 32-bit integer. If so, the
@@ -155,6 +150,11 @@ void
 MacroAssemblerMIPS64Compat::convertFloat32ToInt32(FloatRegister src, Register dest,
                                                   Label* fail, bool negativeZeroCheck)
 {
+    if (negativeZeroCheck) {
+        moveFromFloat32(src, dest);
+        ma_b(dest, Imm32(INT32_MIN), fail, Assembler::Equal);
+    }
+
     // Converting the floating point value to an integer and then converting it
     // back to a float32 would not work, as float to int32 conversions are
     // clamping (e.g. float(INT32_MAX + 1) would get converted into INT32_MAX
@@ -167,17 +167,6 @@ MacroAssemblerMIPS64Compat::convertFloat32ToInt32(FloatRegister src, Register de
 
     // Bail out in the clamped cases.
     ma_b(dest, Imm32(INT32_MAX), fail, Assembler::Equal);
-
-    if (negativeZeroCheck) {
-        Label notZero;
-        ma_b(dest, Imm32(0), &notZero, Assembler::NotEqual, ShortJump);
-        // Test and bail for -0.0, when integer result is 0
-        // Move the top word of the double into the output reg,
-        // if it is non-zero, then the original value was -0.0
-        moveFromDoubleHi(src, dest);
-        ma_b(dest, Imm32(INT32_MIN), fail, Assembler::Equal);
-        bind(&notZero);
-    }
 }
 
 void