mirrors/SDL
1
0
Fork 0
mirror of https://github.com/libsdl-org/SDL.git synced 2026-02-02 18:14:35 +00:00
Code Issues Packages Projects Releases Wiki Activity

Avoid using hex-floats

Browse Source
This commit is contained in:
Brick
2023-08-24 19:49:25 +01:00
committed by Ryan C. Gordon
parent 5b696996cd
commit e44f54ec54
1 changed files with 8 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/audio/SDL_audiotypecvt.c
View File

@@ -39,6 +39,8 @@
#define NEED_SCALAR_CONVERTER_FALLBACKS 1
#endif
#define DIVBY2147483648 0.0000000004656612873077392578125f /* 0x1p-31f */
#if NEED_SCALAR_CONVERTER_FALLBACKS
/* This code requires that floats are in the IEEE-754 binary32 format */
@@ -101,7 +103,7 @@ static void SDL_Convert_S32_to_F32_Scalar(float *dst, const Sint32 *src, int num
LOG_DEBUG_AUDIO_CONVERT("S32", "F32");
for (i = num_samples - 1; i >= 0; --i) {
dst[i] = (float)src[i] * 0x1p-31f;
dst[i] = (float)src[i] * DIVBY2147483648;
}
}
@@ -319,7 +321,7 @@ static void SDL_TARGETING("sse2") SDL_Convert_S32_to_F32_SSE2(float *dst, const
int i = num_samples;
/* dst[i] = f32(src[i]) / f32(0x80000000) */
const __m128 scaler = _mm_set1_ps(0x1p-31f);
const __m128 scaler = _mm_set1_ps(DIVBY2147483648);
LOG_DEBUG_AUDIO_CONVERT("S32", "F32 (using SSE2)");
@@ -493,7 +495,7 @@ static void SDL_TARGETING("sse2") SDL_Convert_F32_to_S32_SSE2(Sint32 *dst, const
* 2) Convert to integer (values too small/large become 0x80000000 = -2147483648)
* 3) Fixup values which were too large (0x80000000 ^ 0xFFFFFFFF = 2147483647)
* dst[i] = i32(src[i] * 2147483648.0) ^ ((src[i] >= 2147483648.0) ? 0xFFFFFFFF : 0x00000000) */
const __m128 limit = _mm_set1_ps(0x1p31f);
const __m128 limit = _mm_set1_ps(2147483648.0f);
LOG_DEBUG_AUDIO_CONVERT("F32", "S32 (using SSE2)");
@@ -537,9 +539,9 @@ static void SDL_TARGETING("sse2") SDL_Convert_F32_to_S32_SSE2(Sint32 *dst, const
#endif
#ifdef SDL_NEON_INTRINSICS
#define DIVBY128 0x1p-7f
#define DIVBY32768 0x1p-15f
#define DIVBY8388607 0x1.000002p-23f
#define DIVBY128 0.0078125f /* 0x1p-7f */
#define DIVBY32768 0.000030517578125f /* 0x1p-15f */
#define DIVBY8388607 0.00000011920930376163766f /* 0x1.000002p-23f */
static void SDL_Convert_S8_to_F32_NEON(float *dst, const Sint8 *src, int num_samples)
{