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Fix compiler warnings

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This commit is contained in:
Ken Cooke 2016-03-01 12:07:28 -08:00
parent 90bf398978
commit 261f5c45de
1 changed files with 6 additions and 67 deletions
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73
libraries/audio/src/AudioLimiter.cpp
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@ -83,6 +83,8 @@ static const int32_t EXP2_BIAS = 64;
// P(x) = log2(1+x) for x=[0,1]
// scaled by 1, 0.5, 0.25
//
// |error| < 347 ulp, smooth
//
static const int LOG2_TABBITS = 4;
static const int32_t log2Table[1 << LOG2_TABBITS][3] = {
{ -0x56dfe26d, 0x5c46daff, 0x00000000 },
@ -106,9 +108,10 @@ static const int32_t log2Table[1 << LOG2_TABBITS][3] = {
//
// P(x) = exp2(x) for x=[0,1]
// scaled by 2, 1, 0.5
//
// Uses exp2(-x) = exp2(1-x)/2
//
// |error| < 1387 ulp, smooth
//
static const int EXP2_TABBITS = 4;
static const int32_t exp2Table[1 << EXP2_TABBITS][3] = {
{ 0x3ed838c8, 0x58b574b7, 0x40000000 },
@ -129,68 +132,6 @@ static const int32_t exp2Table[1 << EXP2_TABBITS][3] = {
{ 0x785c4499, 0x390ecc3a, 0x456188bd },
};
//
// Count Leading Zeros
// defined to match ARM CLZ and x86 LZCNT
//
static inline int CLZ(uint32_t x) {
int e = 0;
if (x == 0) return 32;
if (x < 0x00010000) {
x <<= 16;
e += 16;
}
if (x < 0x01000000) {
x <<= 8;
e += 8;
}
if (x < 0x10000000) {
x <<= 4;
e += 4;
}
if (x < 0x40000000) {
x <<= 2;
e += 2;
}
if (x < 0x80000000) {
e += 1;
}
return e;
}
//
// Compute -log2(x) for x=[0,1] in Q31, result in Q26
// x = 0 returns -log2(1)
// x < 0 undefined
//
// |error| < 347 ulp, smooth
//
static inline int32_t fixlog2(int32_t x) {
// normalize to [0x80000000, 0xffffffff]
int e = CLZ(x);
x <<= e;
e -= e >> LOG2_INTBITS; // if e==32, e=31
// x - 1.0
x &= 0x7fffffff;
int k = x >> (31 - LOG2_TABBITS);
// polynomial for log2(1+x) over x=[0,1]
int32_t c0 = log2Table[k][0];
int32_t c1 = log2Table[k][1];
int32_t c2 = log2Table[k][2];
c1 += MULHI(c0, x);
c2 += MULHI(c1, x);
// reconstruct result in Q26
return (e << LOG2_FRACBITS) - (c2 >> 3);
}
static const int IEEE754_MANT_BITS = 23;
static const int IEEE754_EXPN_BIAS = 127;
@ -214,7 +155,7 @@ static inline int32_t peaklog2(float* input) {
// saturate
if (e > 31) return 0x7fffffff;
int k = x >> (31 - EXP2_TABBITS);
int k = x >> (31 - LOG2_TABBITS);
// polynomial for log2(1+x) over x=[0,1]
int32_t c0 = log2Table[k][0];
@ -251,7 +192,7 @@ static inline int32_t peaklog2(float* input0, float* input1) {
// saturate
if (e > 31) return 0x7fffffff;
int k = x >> (31 - EXP2_TABBITS);
int k = x >> (31 - LOG2_TABBITS);
// polynomial for log2(1+x) over x=[0,1]
int32_t c0 = log2Table[k][0];
@ -269,8 +210,6 @@ static inline int32_t peaklog2(float* input0, float* input1) {
// Compute exp2(-x) for x=[0,32] in Q26, result in Q31
// x < 0 undefined
//
// |error| < 1387 ulp, smooth
//
static inline int32_t fixexp2(int32_t x) {
// split into e and 1.0 - x