From d536ec53bb775fa7286715011167fe25b3561f05 Mon Sep 17 00:00:00 2001
From: Tom Ritter <tom@mozilla.com>
Date: Tue, 10 Dec 2019 18:41:41 +0000
Subject: [PATCH] Bug 1590624 - mingw-clang cannot use _xgetbv without -mavx,
 work around it r=lsalzman,froydnj

Differential Revision: https://phabricator.services.mozilla.com/D54531

--HG--
extra : moz-landing-system : lando
---
 gfx/skia/skia/src/core/SkCpu.cpp |  2 +-
 mozglue/build/SSE.cpp            | 23 +++++++++++------------
 mozglue/build/SSE.h              |  4 ++++
 widget/windows/GfxInfo.cpp       |  5 ++---
 4 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/gfx/skia/skia/src/core/SkCpu.cpp b/gfx/skia/skia/src/core/SkCpu.cpp
index 54bf0c7ca809..bdae9d3a8a65 100644
--- a/gfx/skia/skia/src/core/SkCpu.cpp
+++ b/gfx/skia/skia/src/core/SkCpu.cpp
@@ -11,7 +11,7 @@
 #include "src/core/SkCpu.h"
 
 #if defined(SK_CPU_X86)
-    #if defined(SK_BUILD_FOR_WIN)
+    #if defined(SK_BUILD_FOR_WIN) && !defined(__MINGW32__)
         #include <intrin.h>
         static void cpuid (uint32_t abcd[4]) { __cpuid  ((int*)abcd, 1);    }
         static void cpuid7(uint32_t abcd[4]) { __cpuidex((int*)abcd, 7, 0); }
diff --git a/mozglue/build/SSE.cpp b/mozglue/build/SSE.cpp
index 403c653c817a..b3c9a5722492 100644
--- a/mozglue/build/SSE.cpp
+++ b/mozglue/build/SSE.cpp
@@ -40,14 +40,6 @@ static bool has_cpuid_bits(unsigned int level, CPUIDRegister reg,
   return (regs[reg] & bits) == bits;
 }
 
-#  if !defined(MOZILLA_PRESUME_AVX)
-static uint64_t xgetbv(uint32_t xcr) {
-  uint32_t eax, edx;
-  __asm__(".byte 0x0f, 0x01, 0xd0" : "=a"(eax), "=d"(edx) : "c"(xcr));
-  return (uint64_t)(edx) << 32 | eax;
-}
-#  endif
-
 #elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_AMD64))
 
 enum CPUIDRegister { eax = 0, ebx = 1, ecx = 2, edx = 3 };
@@ -65,10 +57,6 @@ static bool has_cpuid_bits(unsigned int level, CPUIDRegister reg,
   return (unsigned(regs[reg]) & bits) == bits;
 }
 
-#  if !defined(MOZILLA_PRESUME_AVX)
-static uint64_t xgetbv(uint32_t xcr) { return _xgetbv(xcr); }
-#  endif
-
 #elif (defined(__GNUC__) || defined(__SUNPRO_CC)) && \
     (defined(__i386) || defined(__x86_64__))
 
@@ -194,4 +182,15 @@ bool aes_enabled = has_cpuid_bits(1u, ecx, (1u << 25));
 #endif
 
 }  // namespace sse_private
+
+#ifdef HAVE_CPUID_H
+
+uint64_t xgetbv(uint32_t xcr) {
+  uint32_t eax, edx;
+  __asm__(".byte 0x0f, 0x01, 0xd0" : "=a"(eax), "=d"(edx) : "c"(xcr));
+  return (uint64_t)(edx) << 32 | eax;
+}
+
+#endif
+
 }  // namespace mozilla
diff --git a/mozglue/build/SSE.h b/mozglue/build/SSE.h
index bd618c4680b1..8a2e66824754 100644
--- a/mozglue/build/SSE.h
+++ b/mozglue/build/SSE.h
@@ -227,6 +227,10 @@ extern bool MFBT_DATA aes_enabled;
 #endif
 }  // namespace sse_private
 
+#ifdef HAVE_CPUID_H
+MOZ_EXPORT uint64_t xgetbv(uint32_t xcr);
+#endif
+
 #if defined(MOZILLA_PRESUME_MMX)
 #  define MOZILLA_MAY_SUPPORT_MMX 1
 inline bool supports_mmx() { return true; }
diff --git a/widget/windows/GfxInfo.cpp b/widget/windows/GfxInfo.cpp
index 24392a4f62d6..366f9b811b68 100644
--- a/widget/windows/GfxInfo.cpp
+++ b/widget/windows/GfxInfo.cpp
@@ -17,6 +17,7 @@
 #include "mozilla/Preferences.h"
 #include "mozilla/gfx/DeviceManagerDx.h"
 #include "mozilla/gfx/Logging.h"
+#include "mozilla/SSE.h"
 #include "nsExceptionHandler.h"
 #include "nsPrintfCString.h"
 #include "jsapi.h"
@@ -32,8 +33,6 @@ using namespace mozilla::widget;
 NS_IMPL_ISUPPORTS_INHERITED(GfxInfo, GfxInfoBase, nsIGfxInfoDebug)
 #endif
 
-static const uint32_t allWindowsVersions = 0xffffffff;
-
 GfxInfo::GfxInfo()
     : mWindowsVersion(0), mActiveGPUIndex(0), mHasDualGPU(false) {}
 
@@ -1098,7 +1097,7 @@ static inline bool DetectBrokenAVX() {
   }
 
   const unsigned AVX_CTRL_BITS = (1 << 1) | (1 << 2);
-  return (_xgetbv(0) & AVX_CTRL_BITS) != AVX_CTRL_BITS;
+  return (xgetbv(0) & AVX_CTRL_BITS) != AVX_CTRL_BITS;
 }
 #endif