[turbofan] Fixed the second return value of TryTruncateFloatXXToUint64.

src/mips64/macro-assembler-mips64.cc

 // Copyright 2012 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.
 
 #include <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
@@ skipping 1687 matching lines @@
 
 
 void MacroAssembler::Trunc_ul_d(FPURegister fd, Register rs,
                                 FPURegister scratch, Register result) {
   DCHECK(!fd.is(scratch));
   DCHECK(!AreAliased(rs, result, at));
 
   Label simple_convert, done, fail;
   if (result.is_valid()) {
     mov(result, zero_reg);
-    Move(kDoubleRegZero, 0.0);
-    // If fd < 0 or unordered, then the conversion fails.
-    BranchF(&fail, &fail, lt, fd, kDoubleRegZero);
+    Move(scratch, -1.0);
+    // If fd =< -1 or unordered, then the conversion fails.
+    BranchF(&fail, &fail, le, fd, scratch);
   }
 
   // Load 2^63 into scratch as its double representation.
   li(at, 0x43e0000000000000);
   dmtc1(at, scratch);
 
   // Test if scratch > fd.
   // If fd < 2^63 we can convert it normally.
   BranchF(&simple_convert, nullptr, lt, fd, scratch);
 
@@ skipping 25 matching lines @@
 
 
 void MacroAssembler::Trunc_ul_s(FPURegister fd, Register rs,
                                 FPURegister scratch, Register result) {
   DCHECK(!fd.is(scratch));
   DCHECK(!AreAliased(rs, result, at));
 
   Label simple_convert, done, fail;
   if (result.is_valid()) {
     mov(result, zero_reg);
-    Move(kDoubleRegZero, 0.0);
-    // If fd < 0 or unordered, then the conversion fails.
-    BranchF32(&fail, &fail, lt, fd, kDoubleRegZero);
+    Move(scratch, -1.0f);
+    // If fd =< -1 or unordered, then the conversion fails.
+    BranchF32(&fail, &fail, le, fd, scratch);
   }
 
   // Load 2^63 into scratch as its float representation.
   li(at, 0x5f000000);
   mtc1(at, scratch);
 
   // Test if scratch > fd.
   // If fd < 2^63 we can convert it normally.
   BranchF32(&simple_convert, nullptr, lt, fd, scratch);
 
@@ skipping 4552 matching lines @@
   if (mag.shift > 0) sra(result, result, mag.shift);
   srl(at, dividend, 31);
   Addu(result, result, Operand(at));
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64