diff options
| author | Karl Tomlinson <karlt+@karlt.net> | 2020-08-29 03:23:29 +0300 |
|---|---|---|
| committer | Ralph Giles <giles@thaumas.net> | 2020-10-02 19:23:27 +0300 |
| commit | 9617cea1d4d41199a36c664cc268a830aa0f4ba7 (patch) | |
| tree | 53895c44f43b4d213baa3d61a61f333baf40a6e6 | |
| parent | dc6394e975ec00618a90a38bfd95b28b8e48405b (diff) | |
fixed-point: don't truncate 32-bit arg to MULT16_32_Q15
The 32-bit arg and return value have one bit more than required to represent
+/-32767 with 15 fractional bits.
Keeping the most significant bit allows saturation for 16-bit conversion to
sometimes be delayed until after these operations.
| -rw-r--r-- | libspeexdsp/fixed_debug.h | 4 | ||||
| -rw-r--r-- | libspeexdsp/fixed_generic.h | 6 |
2 files changed, 5 insertions, 5 deletions
diff --git a/libspeexdsp/fixed_debug.h b/libspeexdsp/fixed_debug.h index 8b2f2ef..25d4ea7 100644 --- a/libspeexdsp/fixed_debug.h +++ b/libspeexdsp/fixed_debug.h @@ -279,7 +279,7 @@ static inline int _MULT16_32_QX(int a, long long b, int Q, char *file, int line) { fprintf (stderr, "MULT16_32_Q%d: inputs are not short+int: %d %d in %s: line %d\n", Q, (int)a, (int)b, file, line); } - if (ABS32(b)>=(EXTEND32(1)<<(15+Q))) + if (ABS(b)>>(16+Q)) fprintf (stderr, "MULT16_32_Q%d: second operand too large: %d %d in %s: line %d\n", Q, (int)a, (int)b, file, line); res = (((long long)a)*(long long)b) >> Q; if (!VERIFY_INT(res)) @@ -295,7 +295,7 @@ static inline int MULT16_32_PX(int a, long long b, int Q) { fprintf (stderr, "MULT16_32_P%d: inputs are not short+int: %d %d\n", Q, (int)a, (int)b); } - if (ABS32(b)>=(EXTEND32(1)<<(15+Q))) + if (ABS(b)>>(16+Q)) fprintf (stderr, "MULT16_32_Q%d: second operand too large: %d %d\n", Q, (int)a, (int)b); res = ((((long long)a)*(long long)b) + ((EXTEND32(1)<<Q)>>1))>> Q; if (!VERIFY_INT(res)) diff --git a/libspeexdsp/fixed_generic.h b/libspeexdsp/fixed_generic.h index 64f65be..e5d1ce5 100644 --- a/libspeexdsp/fixed_generic.h +++ b/libspeexdsp/fixed_generic.h @@ -76,9 +76,9 @@ #define MAC16_16(c,a,b) (ADD32((c),MULT16_16((a),(b)))) -#define MULT16_32_P15(a,b) ADD32(MULT16_16((a),SHR((b),15)), PSHR(MULT16_16((a),((b)&0x00007fff)),15)) -#define MULT16_32_Q15(a,b) ADD32(MULT16_16((a),SHR((b),15)), SHR(MULT16_16((a),((b)&0x00007fff)),15)) -#define MAC16_32_Q15(c,a,b) ADD32(c,ADD32(MULT16_16((a),SHR((b),15)), SHR(MULT16_16((a),((b)&0x00007fff)),15))) +#define MULT16_32_P15(a,b) ADD32((a)*SHR((b),15), PSHR(MULT16_16((a),((b)&0x00007fff)),15)) +#define MULT16_32_Q15(a,b) ADD32((a)*SHR((b),15), SHR(MULT16_16((a),((b)&0x00007fff)),15)) +#define MAC16_32_Q15(c,a,b) ADD32(c,ADD32((a)*SHR((b),15), SHR(MULT16_16((a),((b)&0x00007fff)),15))) #define MAC16_16_Q11(c,a,b) (ADD32((c),SHR(MULT16_16((a),(b)),11))) |