fix MUL* macros with ()

factor more multiplies in 4-subband encoder

2 files changed, 7 insertions, 14 deletions

diff --git a/sbc/sbc.c b/sbc/sbc.c
index a5cbf803..c262f16d 100644
--- a/sbc/sbc.c
+++ b/sbc/sbc.c
@@ -793,19 +793,12 @@ static inline void _sbc_analyze_four(const int32_t *in, int32_t *out)
 	MULA(res, _anamatrix4[3], t[7]);
 	out[3] = SCALE4_STAGE2(res);
 #else
-	/* some of these multiplies could be factored more but something overflows */
-	/* eg replace the first two lines with MUL(s[0], _anamatrix4[0], t[0] + t[4]) */
-	MUL(s[0], _anamatrix4[0], t[0]);
-	MULA(s[0], _anamatrix4[0], t[4]);
+	MUL(s[0], _anamatrix4[0], t[0] + t[4]);
 	MUL(s[1], _anamatrix4[2], t[2]);
-	MUL(s[2], _anamatrix4[1], t[1]);
-	MULA(s[2], _anamatrix4[1], t[3]);
-	MULA(s[2], _anamatrix4[3], t[5]);
-	MULA(s[2], -_anamatrix4[3], t[7]);
-	MUL(s[3], _anamatrix4[3], t[1]);
-	MULA(s[3], _anamatrix4[3], t[3]);
-	MULA(s[3], -_anamatrix4[1], t[5]);
-	MULA(s[3], _anamatrix4[1], t[7]);
+	MUL(s[2], _anamatrix4[1], t[1] + t[3]);
+	MULA(s[2], _anamatrix4[3], t[5] + t[7]);
+	MUL(s[3], _anamatrix4[3], t[1] + t[3]);
+	MULA(s[3], _anamatrix4[1], - t[5] + t[7]);
 	out[0] = SCALE4_STAGE2( s[0] + s[1] + s[2]);
 	out[1] = SCALE4_STAGE2(-s[0] + s[1] + s[3]);
 	out[2] = SCALE4_STAGE2(-s[0] + s[1] - s[3]);
diff --git a/sbc/sbc_math.h b/sbc/sbc_math.h
index d01799c9..e4f82bce 100644
--- a/sbc/sbc_math.h
+++ b/sbc/sbc_math.h
@@ -64,6 +64,6 @@ typedef long long sbc_extended_t;
 #define SBC_FIXED_0(val) { val = 0; }
 #define ADD(dst, src)    { dst += src; }
 #define SUB(dst, src)    { dst -= src; }
-#define MUL(dst, a, b)   { dst = (sbc_fixed_t) a * b; }
-#define MULA(dst, a, b)  { dst += (sbc_extended_t) a * b; }
+#define MUL(dst, a, b)   { dst = (sbc_fixed_t) (a) * (b); }
+#define MULA(dst, a, b)  { dst += (sbc_extended_t) (a) * (b); }
 #define DIV2(dst, src)   { dst = ASR(src, 1); }