Bug 1105729: Pre VS2010 SP1 define our own verion of _xgetbv. r=tabraldes

security/sandbox/chromium/base/cpu.cc

@@ -51,6 +51,16 @@ CPU::CPU()
 namespace {
 
 #if defined(ARCH_CPU_X86_FAMILY)
+#if defined(_MSC_VER) && (_MSC_FULL_VER < 160040219)
+// Prior to VS2010 SP1, _xgetbv is not defined in immintrin.h, so we need to
+// define our own version using the assembly operation.
+// By using __fastcall we ensure that xcr is already in register ecx for xgetbv
+// and xgetbv populates the correct registers (eax edx) for our return value.
+uint64_t __fastcall _xgetbv(uint32_t xcr) {
+  __asm xgetbv;
+}
+#endif
+
 #ifndef _MSC_VER
 
 #if defined(__pic__) && defined(__i386__)

security/sandbox/modifications-to-chromium-to-reapply-after-upstream-merge.txt

@@ -1,5 +1,6 @@
 Please add a link to the bugzilla bug and patch name that should be re-applied.
 Also, please update any existing links to their actual mozilla-central changeset.
 
-https://bugzilla.mozilla.org/show_bug.cgi?id=1041775 bug1041775part3.patch
-https://bugzilla.mozilla.org/show_bug.cgi?id=928044  bug928044part3.patch
+https://hg.mozilla.org/mozilla-central/rev/365d1073111a
+https://hg.mozilla.org/mozilla-central/rev/0f763c186855
+https://bugzilla.mozilla.org/show_bug.cgi?id=1105729 bug1105729.patch