From 33ebc29337face0f030719960338af3d2654cdf8 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 15 Feb 2011 13:44:49 +0000 Subject: target-arm: Fix unsigned VQRSHL by large shift counts Correctly handle VQRSHL of unsigned values by a shift count of the width of the data type or larger, which must be special-cased in the qrshl_u* helper functions. Signed-off-by: Peter Maydell Signed-off-by: Aurelien Jarno --- target-arm/neon_helper.c | 37 ++++++++++++++++++++++++++++++++++--- 1 file changed, 34 insertions(+), 3 deletions(-) diff --git a/target-arm/neon_helper.c b/target-arm/neon_helper.c index 1b41d4664a..002a9c11a6 100644 --- a/target-arm/neon_helper.c +++ b/target-arm/neon_helper.c @@ -818,7 +818,18 @@ uint64_t HELPER(neon_qshlu_s64)(CPUState *env, uint64_t valop, uint64_t shiftop) #define NEON_FN(dest, src1, src2) do { \ int8_t tmp; \ tmp = (int8_t)src2; \ - if (tmp < 0) { \ + if (tmp >= (ssize_t)sizeof(src1) * 8) { \ + if (src1) { \ + SET_QC(); \ + dest = ~0; \ + } else { \ + dest = 0; \ + } \ + } else if (tmp < -(ssize_t)sizeof(src1) * 8) { \ + dest = 0; \ + } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \ + dest = src1 >> (sizeof(src1) * 8 - 1); \ + } else if (tmp < 0) { \ dest = (src1 + (1 << (-1 - tmp))) >> -tmp; \ } else { \ dest = src1 << tmp; \ @@ -837,7 +848,18 @@ uint32_t HELPER(neon_qrshl_u32)(CPUState *env, uint32_t val, uint32_t shiftop) { uint32_t dest; int8_t shift = (int8_t)shiftop; - if (shift < 0) { + if (shift >= 32) { + if (val) { + SET_QC(); + dest = ~0; + } else { + dest = 0; + } + } else if (shift < -32) { + dest = 0; + } else if (shift == -32) { + dest = val >> 31; + } else if (shift < 0) { uint64_t big_dest = ((uint64_t)val + (1 << (-1 - shift))); dest = big_dest >> -shift; } else { @@ -855,7 +877,16 @@ uint32_t HELPER(neon_qrshl_u32)(CPUState *env, uint32_t val, uint32_t shiftop) uint64_t HELPER(neon_qrshl_u64)(CPUState *env, uint64_t val, uint64_t shiftop) { int8_t shift = (int8_t)shiftop; - if (shift < 0) { + if (shift >= 64) { + if (val) { + SET_QC(); + val = ~0; + } + } else if (shift < -64) { + val = 0; + } else if (shift == -64) { + val >>= 63; + } else if (shift < 0) { val >>= (-shift - 1); if (val == UINT64_MAX) { /* In this case, it means that the rounding constant is 1, -- cgit v1.2.3