Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 131 insertions, 0 deletions

diff --git a/mozglue/build/arm.cpp b/mozglue/build/arm.cpp
new file mode 100644
index 0000000000..a74a41f6c0
--- /dev/null
+++ b/mozglue/build/arm.cpp
@@ -0,0 +1,131 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* compile-time and runtime tests for whether to use various ARM extensions */
+
+#include "arm.h"
+
+#if defined(MOZILLA_ARM_HAVE_CPUID_DETECTION)
+
+// arm.h has parallel #ifs which declare MOZILLA_ARM_HAVE_CPUID_DETECTION.
+// We don't check it here so that we get compile errors if it's defined, but
+// we don't compile one of these detection methods. The detection code here is
+// based on the CPU detection in libtheora.
+
+#  if defined(__linux__) || defined(ANDROID)
+#    include <stdio.h>
+#    include <stdlib.h>
+#    include <string.h>
+
+enum {
+  MOZILLA_HAS_EDSP_FLAG = 1,
+  MOZILLA_HAS_ARMV6_FLAG = 2,
+  MOZILLA_HAS_ARMV7_FLAG = 4,
+  MOZILLA_HAS_NEON_FLAG = 8
+};
+
+static unsigned get_arm_cpu_flags(void) {
+  unsigned flags;
+  FILE* fin;
+  bool armv6_processor = false;
+  flags = 0;
+  /*Reading /proc/self/auxv would be easier, but that doesn't work reliably on
+    Android. This also means that detection will fail in Scratchbox, which is
+    desirable, as NEON does not work in the qemu shipped with the Maemo 5 SDK.
+    I don't know if /proc/self/auxv would do any better in that case, anyway,
+    or if it would return random flags from the host CPU.*/
+  fin = fopen("/proc/cpuinfo", "r");
+  if (fin != nullptr) {
+    /*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) != nullptr) {
+      if (memcmp(buf, "Features", 8) == 0) {
+        char* p;
+        p = strstr(buf, " edsp");
+        if (p != nullptr && (p[5] == ' ' || p[5] == '\n'))
+          flags |= MOZILLA_HAS_EDSP_FLAG;
+        p = strstr(buf, " neon");
+        if (p != nullptr && (p[5] == ' ' || p[5] == '\n'))
+          flags |= MOZILLA_HAS_NEON_FLAG;
+      }
+      if (memcmp(buf, "CPU architecture:", 17) == 0) {
+        int version;
+        version = atoi(buf + 17);
+        if (version >= 6) flags |= MOZILLA_HAS_ARMV6_FLAG;
+        if (version >= 7) flags |= MOZILLA_HAS_ARMV7_FLAG;
+      }
+      /* media/webrtc/trunk/src/system_wrappers/source/cpu_features_arm.c
+       * Unfortunately, it seems that certain ARMv6-based CPUs
+       * report an incorrect architecture number of 7!
+       *
+       * We try to correct this by looking at the 'elf_format'
+       * field reported by the 'Processor' field, which is of the
+       * form of "(v7l)" for an ARMv7-based CPU, and "(v6l)" for
+       * an ARMv6-one.
+       */
+      if (memcmp(buf, "Processor\t:", 11) == 0) {
+        if (strstr(buf, "(v6l)") != 0) {
+          armv6_processor = true;
+        }
+      }
+    }
+    fclose(fin);
+  }
+  if (armv6_processor) {
+    // ARMv6 pretending to be ARMv7? clear flag
+    if (flags & MOZILLA_HAS_ARMV7_FLAG) {
+      flags &= ~MOZILLA_HAS_ARMV7_FLAG;
+    }
+  }
+  return flags;
+}
+
+// Cache a local copy so we only have to read /proc/cpuinfo once.
+static unsigned arm_cpu_flags = get_arm_cpu_flags();
+
+#    if !defined(MOZILLA_PRESUME_EDSP)
+static bool check_edsp(void) {
+  return (arm_cpu_flags & MOZILLA_HAS_EDSP_FLAG) != 0;
+}
+#    endif
+
+#    if !defined(MOZILLA_PRESUME_ARMV6)
+static bool check_armv6(void) {
+  return (arm_cpu_flags & MOZILLA_HAS_ARMV6_FLAG) != 0;
+}
+#    endif
+
+#    if !defined(MOZILLA_PRESUME_ARMV7)
+static bool check_armv7(void) {
+  return (arm_cpu_flags & MOZILLA_HAS_ARMV7_FLAG) != 0;
+}
+#    endif
+
+#    if !defined(MOZILLA_PRESUME_NEON)
+static bool check_neon(void) {
+  return (arm_cpu_flags & MOZILLA_HAS_NEON_FLAG) != 0;
+}
+#    endif
+
+#  endif  // defined(__linux__) || defined(ANDROID)
+
+namespace mozilla {
+namespace arm_private {
+#  if !defined(MOZILLA_PRESUME_EDSP)
+bool edsp_enabled = check_edsp();
+#  endif
+#  if !defined(MOZILLA_PRESUME_ARMV6)
+bool armv6_enabled = check_armv6();
+#  endif
+#  if !defined(MOZILLA_PRESUME_ARMV7)
+bool armv7_enabled = check_armv7();
+#  endif
+#  if !defined(MOZILLA_PRESUME_NEON)
+bool neon_enabled = check_neon();
+#  endif
+}  // namespace arm_private
+}  // namespace mozilla
+
+#endif  // MOZILLA_ARM_HAVE_CPUID_DETECTION