ref: 68afa490ccc2fad1e3492f32119a381b9befc279
parent: 32b302c4950b56b220c0470e1bf9bd29bfafec94
author: Jean-Marc Valin <jmvalin@jmvalin.ca>
date: Wed Jan 25 16:56:48 EST 2017
Avoids undefined behaviour in ARM-optimized code Casting to unsigned to avoid shifting negative values left.
--- a/celt/arm/fixed_armv4.h
+++ b/celt/arm/fixed_armv4.h
@@ -37,7 +37,7 @@
"#MULT16_32_Q16\n\t"
"smull %0, %1, %2, %3\n\t"
: "=&r"(rd_lo), "=&r"(rd_hi)
- : "%r"(b),"r"(a<<16)
+ : "%r"(b),"r"(SHL32(a,16))
);
return rd_hi;
}
@@ -54,10 +54,10 @@
"#MULT16_32_Q15\n\t"
"smull %0, %1, %2, %3\n\t"
: "=&r"(rd_lo), "=&r"(rd_hi)
- : "%r"(b), "r"(a<<16)
+ : "%r"(b), "r"(SHL32(a,16))
);
/*We intentionally don't OR in the high bit of rd_lo for speed.*/
- return rd_hi<<1;
+ return SHL32(rd_hi,1);
}
#define MULT16_32_Q15(a, b) (MULT16_32_Q15_armv4(a, b))
--- a/celt/arm/fixed_armv5e.h
+++ b/celt/arm/fixed_armv5e.h
@@ -59,7 +59,7 @@
: "=r"(res)
: "r"(b), "r"(a)
);
- return res<<1;
+ return SHL32(res,1);
}
#define MULT16_32_Q15(a, b) (MULT16_32_Q15_armv5e(a, b))
@@ -76,7 +76,7 @@
"#MAC16_32_Q15\n\t"
"smlawb %0, %1, %2, %3;\n"
: "=r"(res)
- : "r"(b<<1), "r"(a), "r"(c)
+ : "r"(SHL32(b,1)), "r"(a), "r"(c)
);
return res;
}
--- a/silk/arm/NSQ_neon.h
+++ b/silk/arm/NSQ_neon.h
@@ -28,30 +28,31 @@
#define SILK_NSQ_NEON_H
#include "cpu_support.h"
+#include "SigProc_FIX.h"
#undef silk_short_prediction_create_arch_coef
/* For vectorized calc, reverse a_Q12 coefs, convert to 32-bit, and shift for vqdmulhq_s32. */
static OPUS_INLINE void silk_short_prediction_create_arch_coef_neon(opus_int32 *out, const opus_int16 *in, opus_int order)
{- out[15] = in[0] << 15;
- out[14] = in[1] << 15;
- out[13] = in[2] << 15;
- out[12] = in[3] << 15;
- out[11] = in[4] << 15;
- out[10] = in[5] << 15;
- out[9] = in[6] << 15;
- out[8] = in[7] << 15;
- out[7] = in[8] << 15;
- out[6] = in[9] << 15;
+ out[15] = silk_LSHIFT32(in[0], 15);
+ out[14] = silk_LSHIFT32(in[1], 15);
+ out[13] = silk_LSHIFT32(in[2], 15);
+ out[12] = silk_LSHIFT32(in[3], 15);
+ out[11] = silk_LSHIFT32(in[4], 15);
+ out[10] = silk_LSHIFT32(in[5], 15);
+ out[9] = silk_LSHIFT32(in[6], 15);
+ out[8] = silk_LSHIFT32(in[7], 15);
+ out[7] = silk_LSHIFT32(in[8], 15);
+ out[6] = silk_LSHIFT32(in[9], 15);
if (order == 16)
{- out[5] = in[10] << 15;
- out[4] = in[11] << 15;
- out[3] = in[12] << 15;
- out[2] = in[13] << 15;
- out[1] = in[14] << 15;
- out[0] = in[15] << 15;
+ out[5] = silk_LSHIFT32(in[10], 15);
+ out[4] = silk_LSHIFT32(in[11], 15);
+ out[3] = silk_LSHIFT32(in[12], 15);
+ out[2] = silk_LSHIFT32(in[13], 15);
+ out[1] = silk_LSHIFT32(in[14], 15);
+ out[0] = silk_LSHIFT32(in[15], 15);
}
else
{--- a/silk/arm/macros_armv4.h
+++ b/silk/arm/macros_armv4.h
@@ -28,6 +28,11 @@
#ifndef SILK_MACROS_ARMv4_H
#define SILK_MACROS_ARMv4_H
+/* This macro only avoids the undefined behaviour from a left shift of
+ a negative value. It should only be used in macros that can't include
+ SigProc_FIX.h. In other cases, use silk_LSHIFT32(). */
+#define SAFE_SHL(a,b) ((opus_int32)((opus_uint32)(a) << (b)))
+
/* (a32 * (opus_int32)((opus_int16)(b32))) >> 16 output have to be 32bit int */
#undef silk_SMULWB
static OPUS_INLINE opus_int32 silk_SMULWB_armv4(opus_int32 a, opus_int16 b)
@@ -38,7 +43,7 @@
"#silk_SMULWB\n\t"
"smull %0, %1, %2, %3\n\t"
: "=&r"(rd_lo), "=&r"(rd_hi)
- : "%r"(a), "r"(b<<16)
+ : "%r"(a), "r"(SAFE_SHL(b,16))
);
return rd_hi;
}
@@ -80,7 +85,7 @@
: "=&r"(rd_lo), "=&r"(rd_hi)
: "%r"(a), "r"(b)
);
- return (rd_hi<<16)+(rd_lo>>16);
+ return SAFE_SHL(rd_hi,16)+(rd_lo>>16);
}
#define silk_SMULWW(a, b) (silk_SMULWW_armv4(a, b))
@@ -96,8 +101,10 @@
: "=&r"(rd_lo), "=&r"(rd_hi)
: "%r"(b), "r"(c)
);
- return a+(rd_hi<<16)+(rd_lo>>16);
+ return a+SAFE_SHL(rd_hi,16)+(rd_lo>>16);
}
#define silk_SMLAWW(a, b, c) (silk_SMLAWW_armv4(a, b, c))
+
+#undef SAFE_SHL
#endif /* SILK_MACROS_ARMv4_H */
--- a/silk/arm/macros_armv5e.h
+++ b/silk/arm/macros_armv5e.h
@@ -29,6 +29,11 @@
#ifndef SILK_MACROS_ARMv5E_H
#define SILK_MACROS_ARMv5E_H
+/* This macro only avoids the undefined behaviour from a left shift of
+ a negative value. It should only be used in macros that can't include
+ SigProc_FIX.h. In other cases, use silk_LSHIFT32(). */
+#define SAFE_SHL(a,b) ((opus_int32)((opus_uint32)(a) << (b)))
+
/* (a32 * (opus_int32)((opus_int16)(b32))) >> 16 output have to be 32bit int */
#undef silk_SMULWB
static OPUS_INLINE opus_int32 silk_SMULWB_armv5e(opus_int32 a, opus_int16 b)
@@ -190,7 +195,7 @@
"#silk_CLZ16\n\t"
"clz %0, %1;\n"
: "=r"(res)
- : "r"(in16<<16|0x8000)
+ : "r"(SAFE_SHL(in16,16)|0x8000)
);
return res;
}
@@ -209,5 +214,7 @@
return res;
}
#define silk_CLZ32(in32) (silk_CLZ32_armv5(in32))
+
+#undef SAFE_SHL
#endif /* SILK_MACROS_ARMv5E_H */