[assembler] Fix _xgetbv definition in ia32

Port the fix from https://crrev.com/c/1414858 to ia32. TL;DR, _xgetbv is
a reserved name.

Change-Id: I97cb90ea7d244c02326432cfbfd55419a0a9854a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2543933
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71229}

src/codegen/ia32/assembler-ia32.cc

@@ -81,9 +81,10 @@ Immediate Immediate::EmbeddedStringConstant(const StringConstantBase* str) {
 
 namespace {
 
-#if !V8_LIBC_MSVCRT
-
-V8_INLINE uint64_t _xgetbv(unsigned int xcr) {
+V8_INLINE uint64_t xgetbv(unsigned int xcr) {
+#if V8_LIBC_MSVCRT
+  return _xgetbv(xcr);
+#else
   unsigned eax, edx;
   // Check xgetbv; this uses a .byte sequence instead of the instruction
   // directly because older assemblers do not include support for xgetbv and
@@ -91,12 +92,9 @@ V8_INLINE uint64_t _xgetbv(unsigned int xcr) {
   // used.
   __asm__ volatile(".byte 0x0F, 0x01, 0xD0" : "=a"(eax), "=d"(edx) : "c"(xcr));
   return static_cast<uint64_t>(eax) | (static_cast<uint64_t>(edx) << 32);
+#endif
 }
 
-#define _XCR_XFEATURE_ENABLED_MASK 0
-
-#endif  // !V8_LIBC_MSVCRT
-
 bool OSHasAVXSupport() {
 #if V8_OS_MACOSX
   // Mac OS X up to 10.9 has a bug where AVX transitions were indeed being
@@ -116,7 +114,7 @@ bool OSHasAVXSupport() {
   if (kernel_version_major <= 13) return false;
 #endif  // V8_OS_MACOSX
   // Check whether OS claims to support AVX.
-  uint64_t feature_mask = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
+  uint64_t feature_mask = xgetbv(0);  // XCR_XFEATURE_ENABLED_MASK
   return (feature_mask & 0x6) == 0x6;
 }