ref: 39d6651041e5fb5edfe6a61dc5dd627cdd9b58d8
parent: 863d526efec9afd8091a5b37d8b64e2cb0c2e773
author: Alibek Omarov <a1ba.omarov@gmail.com>
date: Thu Aug 30 18:48:53 EDT 2018
minimp3: add comments after #else, #endif corresponding to their preprocessor macro condition
--- a/minimp3.h
+++ b/minimp3.h
@@ -24,23 +24,23 @@
#ifdef __cplusplus
extern "C" {-#endif
+#endif /* __cplusplus */
void mp3dec_init(mp3dec_t *dec);
#ifndef MINIMP3_FLOAT_OUTPUT
typedef int16_t mp3d_sample_t;
-#else
+#else /* MINIMP3_FLOAT_OUTPUT */
typedef float mp3d_sample_t;
void mp3dec_f32_to_s16(const float *in, int16_t *out, int num_samples);
-#endif
+#endif /* MINIMP3_FLOAT_OUTPUT */
int mp3dec_decode_frame(mp3dec_t *dec, const uint8_t *mp3, int mp3_bytes, mp3d_sample_t *pcm, mp3dec_frame_info_t *info);
#ifdef __cplusplus
}
-#endif
+#endif /* __cplusplus */
#ifdef MINIMP3_IMPLEMENTATION
-
+#error
#include <stdlib.h>
#include <string.h>
@@ -85,12 +85,12 @@
#if !defined(MINIMP3_ONLY_SIMD) && (defined(_M_X64) || defined(_M_ARM64) || defined(__x86_64__) || defined(__aarch64__))
/* x64 always have SSE2, arm64 always have neon, no need for generic code */
#define MINIMP3_ONLY_SIMD
-#endif
+#endif /* SIMD checks... */
#if (defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))) || ((defined(__i386__) || defined(__x86_64__)) && defined(__SSE2__))
#if defined(_MSC_VER)
#include <intrin.h>
-#endif
+#endif /* defined(_MSC_VER) */
#include <immintrin.h>
#define HAVE_SSE 1
#define HAVE_SIMD 1
@@ -107,7 +107,7 @@
typedef __m128 f4;
#if defined(_MSC_VER) || defined(MINIMP3_ONLY_SIMD)
#define minimp3_cpuid __cpuid
-#else
+#else /* defined(_MSC_VER) || defined(MINIMP3_ONLY_SIMD) */
static __inline__ __attribute__((always_inline)) void minimp3_cpuid(int CPUInfo[], const int InfoType)
{#if defined(__PIC__)
@@ -117,26 +117,26 @@
"cpuid\n"
"xchgl %%ebx, %1\n"
"pop %%rbx\n"
-#else
+#else /* defined(__x86_64__) */
"xchgl %%ebx, %1\n"
"cpuid\n"
"xchgl %%ebx, %1\n"
-#endif
+#endif /* defined(__x86_64__) */
: "=a" (CPUInfo[0]), "=r" (CPUInfo[1]), "=c" (CPUInfo[2]), "=d" (CPUInfo[3])
: "a" (InfoType));
-#else
+#else /* defined(__PIC__) */
__asm__ __volatile__(
"cpuid"
: "=a" (CPUInfo[0]), "=b" (CPUInfo[1]), "=c" (CPUInfo[2]), "=d" (CPUInfo[3])
: "a" (InfoType));
-#endif
+#endif /* defined(__PIC__)*/
}
-#endif
+#endif /* defined(_MSC_VER) || defined(MINIMP3_ONLY_SIMD) */
static int have_simd()
{#ifdef MINIMP3_ONLY_SIMD
return 1;
-#else
+#else /* MINIMP3_ONLY_SIMD */
static int g_have_simd;
int CPUInfo[4];
#ifdef MINIMP3_TEST
@@ -143,7 +143,7 @@
static int g_counter;
if (g_counter++ > 100)
return 0;
-#endif
+#endif /* MINIMP3_TEST */
if (g_have_simd)
goto end;
minimp3_cpuid(CPUInfo, 0);
@@ -155,7 +155,7 @@
}
end:
return g_have_simd - 1;
-#endif
+#endif /* MINIMP3_ONLY_SIMD */
}
#elif defined(__ARM_NEON) || defined(__aarch64__)
#include <arm_neon.h>
@@ -175,19 +175,16 @@
{ /* TODO: detect neon for !MINIMP3_ONLY_SIMD */return 1;
}
-#else
+#else /* SIMD checks... */
#define HAVE_SIMD 0
#ifdef MINIMP3_ONLY_SIMD
#error MINIMP3_ONLY_SIMD used, but SSE/NEON not enabled
-#endif
-#endif
-
-#else
-
+#endif /* MINIMP3_ONLY_SIMD */
+#endif /* SIMD checks... */
+#else /* !defined(MINIMP3_NO_SIMD) */
#define HAVE_SIMD 0
+#endif /* !defined(MINIMP3_NO_SIMD) */
-#endif
-
typedef struct
{const uint8_t *buf;
@@ -464,7 +461,7 @@
}
}
}
-#endif
+#endif /* MINIMP3_ONLY_MP3 */
static int L3_read_side_info(bs_t *bs, L3_gr_info_t *gr, const uint8_t *hdr)
{@@ -842,7 +839,7 @@
VSTORE(left + i, VADD(vl, vr));
VSTORE(right + i, VSUB(vl, vr));
}
-#endif
+#endif /* HAVE_SIMD */
for (; i < n; i++)
{float a = left[i];
@@ -975,7 +972,7 @@
vd = VADD(VMUL(vu, vc1), VMUL(vd, vc0));
VSTORE(grbuf + 14 - i, VREV(vd));
}
-#endif
+#endif /* HAVE_SIMD */
#ifndef MINIMP3_ONLY_SIMD
for(; i < 8; i++)
{@@ -984,7 +981,7 @@
grbuf[18 + i] = u*g_aa[0][i] - d*g_aa[1][i];
grbuf[17 - i] = u*g_aa[1][i] + d*g_aa[0][i];
}
-#endif
+#endif /* MINIMP3_ONLY_SIMD */
}
}
@@ -1073,7 +1070,7 @@
vsum = VADD(VMUL(vovl, vw1), VMUL(vsum, vw0));
VSTORE(grbuf + 14 - i, VREV(vsum));
}
-#endif
+#endif /* HAVE_SIMD */
for (; i < 9; i++)
{float ovl = overlap[i];
@@ -1273,9 +1270,9 @@
{#if HAVE_SSE
#define VSAVE2(i, v) _mm_storel_pi((__m64 *)(void*)&y[i*18], v)
-#else
+#else /* HAVE_SSE */
#define VSAVE2(i, v) vst1_f32((float32_t *)&y[i*18], vget_low_f32(v))
-#endif
+#endif /* HAVE_SSE */
for (i = 0; i < 7; i++, y += 4*18)
{f4 s = VADD(t[3][i], t[3][i + 1]);
@@ -1305,10 +1302,10 @@
VSAVE4(3, t[3][7]);
}
} else
-#endif
+#endif /* HAVE_SIMD */
#ifdef MINIMP3_ONLY_SIMD
{}-#else
+#else /* MINIMP3_ONLY_SIMD */
for (; k < n; k++)
{float t[4][8], *x, *y = grbuf + k;
@@ -1367,7 +1364,7 @@
y[2*18] = t[1][7];
y[3*18] = t[3][7];
}
-#endif
+#endif /* MINIMP3_ONLY_SIMD */
}
#ifndef MINIMP3_FLOAT_OUTPUT
@@ -1379,12 +1376,12 @@
s -= (s < 0); /* away from zero, to be compliant */
return s;
}
-#else
+#else /* MINIMP3_FLOAT_OUTPUT */
static float mp3d_scale_pcm(float sample)
{return sample*(1.f/32768.f);
}
-#endif
+#endif /* MINIMP3_FLOAT_OUTPUT */
static void mp3d_synth_pair(mp3d_sample_t *pcm, int nch, const float *z)
{@@ -1486,7 +1483,7 @@
dstr[(49 + i)*nch] = _mm_extract_epi16(pcm8, 7);
dstl[(47 - i)*nch] = _mm_extract_epi16(pcm8, 2);
dstl[(49 + i)*nch] = _mm_extract_epi16(pcm8, 6);
-#else
+#else /* HAVE_SSE */
int16x4_t pcma, pcmb;
a = VADD(a, VSET(0.5f));
b = VADD(b, VSET(0.5f));
@@ -1500,9 +1497,9 @@
vst1_lane_s16(dstr + (49 + i)*nch, pcmb, 3);
vst1_lane_s16(dstl + (47 - i)*nch, pcma, 2);
vst1_lane_s16(dstl + (49 + i)*nch, pcmb, 2);
-#endif
+#endif /* HAVE_SSE */
-#else
+#else /* MINIMP3_FLOAT_OUTPUT */
static const f4 g_scale = { 1.0f/32768.0f, 1.0f/32768.0f, 1.0f/32768.0f, 1.0f/32768.0f };a = VMUL(a, g_scale);
@@ -1516,7 +1513,7 @@
_mm_store_ss(dstr + (49 + i)*nch, _mm_shuffle_ps(b, b, _MM_SHUFFLE(3, 3, 3, 3)));
_mm_store_ss(dstl + (47 - i)*nch, _mm_shuffle_ps(a, a, _MM_SHUFFLE(2, 2, 2, 2)));
_mm_store_ss(dstl + (49 + i)*nch, _mm_shuffle_ps(b, b, _MM_SHUFFLE(2, 2, 2, 2)));
-#else
+#else /* HAVE_SSE */
vst1q_lane_f32(dstr + (15 - i)*nch, a, 1);
vst1q_lane_f32(dstr + (17 + i)*nch, b, 1);
vst1q_lane_f32(dstl + (15 - i)*nch, a, 0);
@@ -1525,14 +1522,14 @@
vst1q_lane_f32(dstr + (49 + i)*nch, b, 3);
vst1q_lane_f32(dstl + (47 - i)*nch, a, 2);
vst1q_lane_f32(dstl + (49 + i)*nch, b, 2);
-#endif
+#endif /* HAVE_SSE */
#endif /* MINIMP3_FLOAT_OUTPUT */
}
} else
-#endif
+#endif /* HAVE_SIMD */
#ifdef MINIMP3_ONLY_SIMD
{}-#else
+#else /* MINIMP3_ONLY_SIMD */
for (i = 14; i >= 0; i--)
{#define LOAD(k) float w0 = *w++; float w1 = *w++; float *vz = &zlin[4*i - k*64]; float *vy = &zlin[4*i - (15 - k)*64];
@@ -1561,7 +1558,7 @@
dstl[(47 - i)*nch] = mp3d_scale_pcm(a[2]);
dstl[(49 + i)*nch] = mp3d_scale_pcm(b[2]);
}
-#endif
+#endif /* MINIMP3_ONLY_SIMD */
}
static void mp3d_synth_granule(float *qmf_state, float *grbuf, int nbands, int nch, mp3d_sample_t *pcm, float *lins)
@@ -1586,7 +1583,7 @@
qmf_state[i] = lins[nbands*64 + i];
}
} else
-#endif
+#endif /* MINIMP3_NONSTANDARD_BUT_LOGICAL */
{memcpy(qmf_state, lins + nbands*64, sizeof(float)*15*64);
}
@@ -1716,7 +1713,7 @@
{#ifdef MINIMP3_ONLY_MP3
return 0;
-#else
+#else /* MINIMP3_ONLY_MP3 */
L12_scale_info sci[1];
L12_read_scale_info(hdr, bs_frame, sci);
@@ -1737,7 +1734,7 @@
return 0;
}
}
-#endif
+#endif /* MINIMP3_ONLY_MP3 */
}
return success*hdr_frame_samples(dec->header);
}
@@ -1769,7 +1766,7 @@
out[i+5] = _mm_extract_epi16(pcm8, 5);
out[i+6] = _mm_extract_epi16(pcm8, 6);
out[i+7] = _mm_extract_epi16(pcm8, 7);
-#else
+#else /* HAVE_SSE */
int16x4_t pcma, pcmb;
a = VADD(a, VSET(0.5f));
b = VADD(b, VSET(0.5f));
@@ -1783,9 +1780,9 @@
vst1_lane_s16(out+i+5, pcmb, 1);
vst1_lane_s16(out+i+6, pcmb, 2);
vst1_lane_s16(out+i+7, pcmb, 3);
-#endif
+#endif /* HAVE_SSE */
}
-#endif
+#endif /* HAVE_SIMD */
for(; i < num_samples; i++)
{float sample = in[i] * 32768.0f;
@@ -1802,7 +1799,6 @@
}
}
}
-#endif
-
-#endif /*MINIMP3_IMPLEMENTATION*/
-#endif /*MINIMP3_H*/
+#endif /* MINIMP3_FLOAT_OUTPUT */
+#endif /* MINIMP3_IMPLEMENTATION */
+#endif /* MINIMP3_H */