Support saturation with shift=0.

This patch fixes corner-case saturations, when the target range is
zero. It merely removes the guard against (sh == 0), and makes:
__ssat(0x87654321, 1) return 0xffffffff and set the saturation flag
__usat(0x87654321, 0) return 0 and set the saturation flag

Signed-off-by: Christophe Lyon <christophe.lyon@st.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
This commit is contained in:
Christophe Lyon 2011-01-19 17:10:52 +01:00 committed by Aurelien Jarno
parent e3f114f761
commit 40d3c43360
1 changed files with 12 additions and 16 deletions

View File

@ -6888,27 +6888,23 @@ static void disas_arm_insn(CPUState * env, DisasContext *s)
tcg_gen_shli_i32(tmp, tmp, shift);
}
sh = (insn >> 16) & 0x1f;
if (sh != 0) {
tmp2 = tcg_const_i32(sh);
if (insn & (1 << 22))
gen_helper_usat(tmp, tmp, tmp2);
else
gen_helper_ssat(tmp, tmp, tmp2);
tcg_temp_free_i32(tmp2);
}
tmp2 = tcg_const_i32(sh);
if (insn & (1 << 22))
gen_helper_usat(tmp, tmp, tmp2);
else
gen_helper_ssat(tmp, tmp, tmp2);
tcg_temp_free_i32(tmp2);
store_reg(s, rd, tmp);
} else if ((insn & 0x00300fe0) == 0x00200f20) {
/* [us]sat16 */
tmp = load_reg(s, rm);
sh = (insn >> 16) & 0x1f;
if (sh != 0) {
tmp2 = tcg_const_i32(sh);
if (insn & (1 << 22))
gen_helper_usat16(tmp, tmp, tmp2);
else
gen_helper_ssat16(tmp, tmp, tmp2);
tcg_temp_free_i32(tmp2);
}
tmp2 = tcg_const_i32(sh);
if (insn & (1 << 22))
gen_helper_usat16(tmp, tmp, tmp2);
else
gen_helper_ssat16(tmp, tmp, tmp2);
tcg_temp_free_i32(tmp2);
store_reg(s, rd, tmp);
} else if ((insn & 0x00700fe0) == 0x00000fa0) {
/* Select bytes. */