Commit acdf01ef authored by Christophe Lyon's avatar Christophe Lyon Committed by Aurelien Jarno
Browse files

target-arm: fix VSHLL Neon instruction.



Fix bit mask used when widening the result of shift on narrow input.
Signed-off-by: default avatarChristophe Lyon <christophe.lyon@st.com>
Reviewed-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: default avatarAurelien Jarno <aurelien@aurel32.net>
parent efd41037
......@@ -4880,16 +4880,28 @@ static int disas_neon_data_insn(CPUState * env, DisasContext *s, uint32_t insn)
/* The shift is less than the width of the source
type, so we can just shift the whole register. */
tcg_gen_shli_i64(cpu_V0, cpu_V0, shift);
/* Widen the result of shift: we need to clear
* the potential overflow bits resulting from
* left bits of the narrow input appearing as
* right bits of left the neighbour narrow
* input. */
if (size < 2 || !u) {
uint64_t imm64;
if (size == 0) {
imm = (0xffu >> (8 - shift));
imm |= imm << 16;
} else {
} else if (size == 1) {
imm = 0xffff >> (16 - shift);
} else {
/* size == 2 */
imm = 0xffffffff >> (32 - shift);
}
if (size < 2) {
imm64 = imm | (((uint64_t)imm) << 32);
} else {
imm64 = imm;
}
imm64 = imm | (((uint64_t)imm) << 32);
tcg_gen_andi_i64(cpu_V0, cpu_V0, imm64);
tcg_gen_andi_i64(cpu_V0, cpu_V0, ~imm64);
}
}
neon_store_reg64(cpu_V0, rd + pass);
......
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