Index: source/row_win.cc |
diff --git a/source/row_win.cc b/source/row_win.cc |
index 2a3da8969f1f51937271f2bdc25b27046fb6c512..d54f05e29e6b3e4a33918293d2f442d1aacc65b3 100644 |
--- a/source/row_win.cc |
+++ b/source/row_win.cc |
@@ -6095,6 +6095,36 @@ void ARGBPolynomialRow_AVX2(const uint8* src_argb, |
} |
#endif // HAS_ARGBPOLYNOMIALROW_AVX2 |
+// Samples assumed to be unsigned in low 9, 10 or 12 bits. Scale factor |
+// adjust the sample range to 0 to 1 using a float multiply. |
+// e.g. 9 bit scale is 1.0f / 512.0f |
+// e.g. 10 bit scale is 1.0f / 1024.0f |
+#ifdef HAS_SHORTTOHALFFLOAT_AVX2 |
+__declspec(naked) |
+void ShortToF16Row_AVX2(const uint16* src, int16* dst, float scale, int width) { |
+ __asm { |
+ mov eax, [esp + 4] /* src */ |
+ mov edx, [esp + 8] /* dst */ |
+ vbroadcastss ymm4, [esp + 12] /* scale */ |
+ mov ecx, [esp + 16] /* width */ |
+ |
+ // 8 pixel loop. |
+ convertloop: |
+ vpmovzxwd ymm0, xmmword ptr [eax] // 8 shorts -> 8 ints |
fbarchard1
2016/09/27 22:14:19
note vpmovzxwd is avx2 but other instructions are
|
+ lea eax, [eax + 16] |
+ vcvtdq2ps ymm0, ymm0 // convert 8 ints to floats |
+ vmulps ymm0, ymm0, ymm4 // scale to normalized range 0 to 1 |
+ vcvtps2ph xmm0, ymm0, 0 // float conver to 8 half floats round even |
+ vmovdqu [edx], xmm0 |
+ lea edx, [edx + 16] |
+ sub ecx, 8 |
+ jg convertloop |
+ vzeroupper |
+ ret |
+ } |
+} |
+#endif // HAS_SHORTTOHALFFLOAT_AVX2 |
+ |
#ifdef HAS_ARGBCOLORTABLEROW_X86 |
// Tranform ARGB pixels with color table. |
__declspec(naked) |