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-rw-r--r--third_party/aom/aom_ports/arm_cpudetect.c150
1 files changed, 150 insertions, 0 deletions
diff --git a/third_party/aom/aom_ports/arm_cpudetect.c b/third_party/aom/aom_ports/arm_cpudetect.c
new file mode 100644
index 0000000000..5a75bb3484
--- /dev/null
+++ b/third_party/aom/aom_ports/arm_cpudetect.c
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2016, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include "aom_ports/arm.h"
+#include "config/aom_config.h"
+
+#ifdef WINAPI_FAMILY
+#include <winapifamily.h>
+#if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
+#define getenv(x) NULL
+#endif
+#endif
+
+static int arm_cpu_env_flags(int *flags) {
+ char *env;
+ env = getenv("AOM_SIMD_CAPS");
+ if (env && *env) {
+ *flags = (int)strtol(env, NULL, 0);
+ return 0;
+ }
+ *flags = 0;
+ return -1;
+}
+
+static int arm_cpu_env_mask(void) {
+ char *env;
+ env = getenv("AOM_SIMD_CAPS_MASK");
+ return env && *env ? (int)strtol(env, NULL, 0) : ~0;
+}
+
+#if !CONFIG_RUNTIME_CPU_DETECT
+
+int aom_arm_cpu_caps(void) {
+ /* This function should actually be a no-op. There is no way to adjust any of
+ * these because the RTCD tables do not exist: the functions are called
+ * statically */
+ int flags;
+ int mask;
+ if (!arm_cpu_env_flags(&flags)) {
+ return flags;
+ }
+ mask = arm_cpu_env_mask();
+#if HAVE_NEON
+ flags |= HAS_NEON;
+#endif /* HAVE_NEON */
+ return flags & mask;
+}
+
+#elif defined(_MSC_VER) /* end !CONFIG_RUNTIME_CPU_DETECT */
+/*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/
+#define WIN32_LEAN_AND_MEAN
+#define WIN32_EXTRA_LEAN
+#include <windows.h>
+
+int aom_arm_cpu_caps(void) {
+ int flags;
+ int mask;
+ if (!arm_cpu_env_flags(&flags)) {
+ return flags;
+ }
+ mask = arm_cpu_env_mask();
+/* MSVC has no inline __asm support for ARM, but it does let you __emit
+ * instructions via their assembled hex code.
+ * All of these instructions should be essentially nops.
+ */
+#if HAVE_NEON
+ if (mask & HAS_NEON) {
+ __try {
+ /*VORR q0,q0,q0*/
+ __emit(0xF2200150);
+ flags |= HAS_NEON;
+ } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
+ /*Ignore exception.*/
+ }
+ }
+#endif /* HAVE_NEON */
+ return flags & mask;
+}
+
+#elif defined(__ANDROID__) /* end _MSC_VER */
+#include <cpu-features.h>
+
+int aom_arm_cpu_caps(void) {
+ int flags;
+ int mask;
+ uint64_t features;
+ if (!arm_cpu_env_flags(&flags)) {
+ return flags;
+ }
+ mask = arm_cpu_env_mask();
+ features = android_getCpuFeatures();
+
+#if HAVE_NEON
+ if (features & ANDROID_CPU_ARM_FEATURE_NEON) flags |= HAS_NEON;
+#endif /* HAVE_NEON */
+ return flags & mask;
+}
+
+#elif defined(__linux__) /* end __ANDROID__ */
+
+#include <stdio.h>
+
+int aom_arm_cpu_caps(void) {
+ FILE *fin;
+ int flags;
+ int mask;
+ if (!arm_cpu_env_flags(&flags)) {
+ return flags;
+ }
+ mask = arm_cpu_env_mask();
+ /* Reading /proc/self/auxv would be easier, but that doesn't work reliably
+ * on Android.
+ * This also means that detection will fail in Scratchbox.
+ */
+ fin = fopen("/proc/cpuinfo", "r");
+ if (fin != NULL) {
+ /* 512 should be enough for anybody (it's even enough for all the flags
+ * that x86 has accumulated... so far).
+ */
+ char buf[512];
+ while (fgets(buf, 511, fin) != NULL) {
+#if HAVE_NEON
+ if (memcmp(buf, "Features", 8) == 0) {
+ char *p;
+ p = strstr(buf, " neon");
+ if (p != NULL && (p[5] == ' ' || p[5] == '\n')) {
+ flags |= HAS_NEON;
+ }
+ }
+#endif /* HAVE_NEON */
+ }
+ fclose(fin);
+ }
+ return flags & mask;
+}
+#else /* end __linux__ */
+#error \
+ "--enable-runtime-cpu-detect selected, but no CPU detection method " \
+"available for your platform. Reconfigure with --disable-runtime-cpu-detect."
+#endif