MIPS: Fix 'MIPS: Followup [turbofan] Introduce new operators...

MIPS: Fix 'MIPS: Followup [turbofan] Introduce new operators Float32SubPreserveNan and Float64SubPreserveNan.'

Port eff959bb

Original commit message:
Float32SubMinusZero and Float64SubMinusZero tests are failing because MIPS does not preserve NaN payload according to Wasm spec. Implemented macro-assembler methods that check for NaN operands, and return the qNaN value with preserved payload and sign bits.

TEST=cctest/test-run-wasm/Run_WasmFloat32SubMinusZero, cctest/test-run-wasm/Run_WasmFloat64SubMinusZero
BUG=

Review-Url: https://codereview.chromium.org/2081993002
Cr-Commit-Position: refs/heads/master@{#37151}

src/mips/macro-assembler-mips.cc

@@ -23,14 +23,13 @@ const uint32_t kDoubleSignMask = HeapNumber::kSignMask;
 const uint32_t kDoubleExponentShift = HeapNumber::kExponentShift;
 const uint32_t kDoubleNaNShift = kDoubleExponentShift - 1;
 const uint32_t kDoubleNaNMask =
-    kDoubleSignMask | HeapNumber::kExponentMask | (1 << kDoubleNaNShift);
+    HeapNumber::kExponentMask | (1 << kDoubleNaNShift);
 
 const uint32_t kSingleSignMask = kBinary32SignMask;
 const uint32_t kSingleExponentMask = kBinary32ExponentMask;
 const uint32_t kSingleExponentShift = kBinary32ExponentShift;
 const uint32_t kSingleNaNShift = kSingleExponentShift - 1;
-const uint32_t kSingleNaNMask =
-    kSingleSignMask | kSingleExponentMask | (1 << kSingleNaNShift);
+const uint32_t kSingleNaNMask = kSingleExponentMask | (1 << kSingleNaNShift);
 
 MacroAssembler::MacroAssembler(Isolate* arg_isolate, void* buffer, int size,
                                CodeObjectRequired create_code_object)

src/mips64/macro-assembler-mips64.cc

@@ -21,15 +21,13 @@ namespace internal {
 const uint64_t kDoubleSignMask = Double::kSignMask;
 const uint32_t kDoubleExponentShift = HeapNumber::kMantissaBits;
 const uint32_t kDoubleNaNShift = kDoubleExponentShift - 1;
-const uint64_t kDoubleNaNMask =
-    kDoubleSignMask | Double::kExponentMask | (1L << kDoubleNaNShift);
+const uint64_t kDoubleNaNMask = Double::kExponentMask | (1L << kDoubleNaNShift);
 
 const uint32_t kSingleSignMask = kBinary32SignMask;
 const uint32_t kSingleExponentMask = kBinary32ExponentMask;
 const uint32_t kSingleExponentShift = kBinary32ExponentShift;
 const uint32_t kSingleNaNShift = kSingleExponentShift - 1;
-const uint32_t kSingleNaNMask =
-    kSingleSignMask | kSingleExponentMask | (1 << kSingleNaNShift);
+const uint32_t kSingleNaNMask = kSingleExponentMask | (1 << kSingleNaNShift);
 
 MacroAssembler::MacroAssembler(Isolate* arg_isolate, void* buffer, int size,
                                CodeObjectRequired create_code_object)