Tidy up to enable C4800 on Windows

snapshot/cpu_context.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 22 matching lines @@
   };
 
   // The x87 tag word (in both abridged and full form) identifies physical
   // registers, but |st_mm| is arranged in logical stack order. In order to map
   // physical tag word bits to the logical stack registers they correspond to,
   // the “stack top” value from the x87 status word is necessary.
   int stack_top = (fsw >> 11) & 0x7;
 
   uint16_t fsave_tag = 0;
   for (int physical_index = 0; physical_index < 8; ++physical_index) {
-    bool fxsave_bit = fxsave_tag & (1 << physical_index);
+    bool fxsave_bit = (fxsave_tag & (1 << physical_index)) != 0;
     uint8_t fsave_bits;
 
     if (fxsave_bit) {
       int st_index = (physical_index + 8 - stack_top) % 8;
       const CPUContextX86::X87Register& st = st_mm[st_index].st;
 
       uint32_t exponent = ((st[9] & 0x7f) << 8) | st[8];
       if (exponent == 0x7fff) {
         // Infinity, NaN, pseudo-infinity, or pseudo-NaN. If it was important to
         // distinguish between these, the J bit and the M bit (the most
         // significant bit of |fraction|) could be consulted.
         fsave_bits = kX87TagSpecial;
       } else {
         // The integer bit the “J bit”.
-        bool integer_bit = st[7] & 0x80;
+        bool integer_bit = (st[7] & 0x80) != 0;
         if (exponent == 0) {
           uint64_t fraction = ((implicit_cast<uint64_t>(st[7]) & 0x7f) << 56) |
                               (implicit_cast<uint64_t>(st[6]) << 48) |
                               (implicit_cast<uint64_t>(st[5]) << 40) |
                               (implicit_cast<uint64_t>(st[4]) << 32) |
                               (implicit_cast<uint32_t>(st[3]) << 24) |
                               (st[2] << 16) | (st[1] << 8) | st[0];
           if (!integer_bit && fraction == 0) {
             fsave_bits = kX87TagZero;
           } else {
@@ skipping 23 matching lines @@
       return x86->eip;
     case kCPUArchitectureX86_64:
       return x86_64->rip;
     default:
       NOTREACHED();
       return ~0ull;
   }
 }
 
 }  // namespace crashpad