Add starboardized CPU detection to WebP (youtube#835)

* Add Starboardized CPU detection to WebP b/290060548
TyHolc · Jul 10, 2023 · 4e1e814 · 4e1e814
1 parent a2755fb
commit 4e1e814
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diff --git a/third_party/libwebp/BUILD.gn b/third_party/libwebp/BUILD.gn
@@ -43,6 +43,9 @@ libwebp_lib("libwebp_dsp_dec_common") {
     ":libwebp_dsp_dec_sse2",
     ":libwebp_dsp_dec_sse41",
   ]
+  if (is_starboard) {
+    deps += [ "//starboard:starboard_headers_only" ]
+  }
 }
 
 libwebp_lib("libwebp_dsp_dec_msa") {
@@ -87,6 +90,31 @@ libwebp_lib("libwebp_utils_enc") {
 
 config("libwebp_direct_config") {
   include_dirs = [ "." ]
+  if (is_starboard) {
+    if (current_cpu == "x64" || current_cpu == "x86") {
+      cflags = [
+        "-msse2",
+        "-msse4.1",
+      ]
+      defines = [
+        "WEBP_HAVE_SSE2",
+        "WEBP_HAVE_SSE41",
+      ]
+    }
+
+    # This crashes on x86/Atom, enable on 64-bit only.
+    if (current_cpu == "x64") {
+      cflags += [
+        "-mavx",
+        "-mavx2",
+      ]
+      defines += [ "WEBP_HAVE_AVX2" ]
+    }
+    if (current_cpu == "arm" || current_cpu == "arm64") {
+      defines = [ "WEBP_HAVE_NEON" ]
+      cflags = [ "-mfpu=neon" ]
+    }
+  }
 }
 
 group("libwebp") {

diff --git a/third_party/libwebp/src/dsp/cpu.c b/third_party/libwebp/src/dsp/cpu.c
@@ -13,6 +13,51 @@
 
 #include "src/dsp/dsp.h"
 
+#if defined(STARBOARD)
+
+#include "starboard/cpu_features.h"
+#include "starboard/log.h"
+#include "starboard/system.h"
+
+bool warn_if_not_enabled(const char* name, bool value) {
+  if (!value) {
+    SbLogFormatF("LibWebP optimization not enabled: %s\n", name);
+    SbLogFlush();
+  }
+  return value;
+}
+
+static int StarboardGetCPUInfo(CPUFeature feature) {
+  SbCPUFeatures features;
+  if (SbCPUFeaturesGet(&features)) {
+    switch (feature) {
+      case kSSE2:
+        return warn_if_not_enabled("sse2", features.x86.has_sse2);
+      case kSSE3:
+        return warn_if_not_enabled("sse3", features.x86.has_sse3);
+      case kSSE4_1:
+        return warn_if_not_enabled("sse41", features.x86.has_sse41);
+      case kAVX:
+        return warn_if_not_enabled("avx", features.x86.has_avx);
+      case kAVX2:
+        return warn_if_not_enabled("avx2", features.x86.has_avx2);
+      case kNEON: {
+        return warn_if_not_enabled("neon", features.arm.has_neon);
+      }
+      default:
+        return 0;
+    }
+  } else {
+    SbLogFormatF("LibWebP CPU feature detection failed\n");
+    SbLogFlush();
+  }
+  return 0;
+}
+
+VP8CPUInfo VP8GetCPUInfo = StarboardGetCPUInfo;
+
+#else  // STARBOARD
+
 #if defined(WEBP_HAVE_NEON_RTCD)
 #include <stdio.h>
 #include <string.h>
@@ -220,3 +265,5 @@ VP8CPUInfo VP8GetCPUInfo = mipsCPUInfo;
 #else
 VP8CPUInfo VP8GetCPUInfo = NULL;
 #endif
+
+#endif  // STARBOARD