target-arm: A64: Handle saturating left shifts SQSHL, SQSHLU, UQSHL

Implement the saturating left shift instructions SQSHL, SQSHLU
and UQSHL for the scalar-shift-imm and shift-imm categories.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1394822294-14837-18-git-send-email-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2014-03-17 16:31:51 +00:00
parent 14dcdac82f
commit a847f32c04

View File

@ -76,6 +76,7 @@ typedef struct AArch64DecodeTable {
typedef void NeonGenTwoOpFn(TCGv_i32, TCGv_i32, TCGv_i32);
typedef void NeonGenTwoOpEnvFn(TCGv_i32, TCGv_ptr, TCGv_i32, TCGv_i32);
typedef void NeonGenTwo64OpFn(TCGv_i64, TCGv_i64, TCGv_i64);
typedef void NeonGenTwo64OpEnvFn(TCGv_i64, TCGv_ptr, TCGv_i64, TCGv_i64);
typedef void NeonGenNarrowFn(TCGv_i32, TCGv_i64);
typedef void NeonGenNarrowEnvFn(TCGv_i32, TCGv_ptr, TCGv_i64);
typedef void NeonGenWidenFn(TCGv_i64, TCGv_i32);
@ -6019,6 +6020,121 @@ static void handle_vec_simd_sqshrn(DisasContext *s, bool is_scalar, bool is_q,
return;
}
/* SQSHLU, UQSHL, SQSHL: saturating left shifts */
static void handle_simd_qshl(DisasContext *s, bool scalar, bool is_q,
bool src_unsigned, bool dst_unsigned,
int immh, int immb, int rn, int rd)
{
int immhb = immh << 3 | immb;
int size = 32 - clz32(immh) - 1;
int shift = immhb - (8 << size);
int pass;
assert(immh != 0);
assert(!(scalar && is_q));
if (!scalar) {
if (!is_q && extract32(immh, 3, 1)) {
unallocated_encoding(s);
return;
}
/* Since we use the variable-shift helpers we must
* replicate the shift count into each element of
* the tcg_shift value.
*/
switch (size) {
case 0:
shift |= shift << 8;
/* fall through */
case 1:
shift |= shift << 16;
break;
case 2:
case 3:
break;
default:
g_assert_not_reached();
}
}
if (size == 3) {
TCGv_i64 tcg_shift = tcg_const_i64(shift);
static NeonGenTwo64OpEnvFn * const fns[2][2] = {
{ gen_helper_neon_qshl_s64, gen_helper_neon_qshlu_s64 },
{ NULL, gen_helper_neon_qshl_u64 },
};
NeonGenTwo64OpEnvFn *genfn = fns[src_unsigned][dst_unsigned];
int maxpass = is_q ? 2 : 1;
for (pass = 0; pass < maxpass; pass++) {
TCGv_i64 tcg_op = tcg_temp_new_i64();
read_vec_element(s, tcg_op, rn, pass, MO_64);
genfn(tcg_op, cpu_env, tcg_op, tcg_shift);
write_vec_element(s, tcg_op, rd, pass, MO_64);
tcg_temp_free_i64(tcg_op);
}
tcg_temp_free_i64(tcg_shift);
if (!is_q) {
clear_vec_high(s, rd);
}
} else {
TCGv_i32 tcg_shift = tcg_const_i32(shift);
static NeonGenTwoOpEnvFn * const fns[2][2][3] = {
{
{ gen_helper_neon_qshl_s8,
gen_helper_neon_qshl_s16,
gen_helper_neon_qshl_s32 },
{ gen_helper_neon_qshlu_s8,
gen_helper_neon_qshlu_s16,
gen_helper_neon_qshlu_s32 }
}, {
{ NULL, NULL, NULL },
{ gen_helper_neon_qshl_u8,
gen_helper_neon_qshl_u16,
gen_helper_neon_qshl_u32 }
}
};
NeonGenTwoOpEnvFn *genfn = fns[src_unsigned][dst_unsigned][size];
TCGMemOp memop = scalar ? size : MO_32;
int maxpass = scalar ? 1 : is_q ? 4 : 2;
for (pass = 0; pass < maxpass; pass++) {
TCGv_i32 tcg_op = tcg_temp_new_i32();
read_vec_element_i32(s, tcg_op, rn, pass, memop);
genfn(tcg_op, cpu_env, tcg_op, tcg_shift);
if (scalar) {
switch (size) {
case 0:
tcg_gen_ext8u_i32(tcg_op, tcg_op);
break;
case 1:
tcg_gen_ext16u_i32(tcg_op, tcg_op);
break;
case 2:
break;
default:
g_assert_not_reached();
}
write_fp_sreg(s, rd, tcg_op);
} else {
write_vec_element_i32(s, tcg_op, rd, pass, MO_32);
}
tcg_temp_free_i32(tcg_op);
}
tcg_temp_free_i32(tcg_shift);
if (!is_q && !scalar) {
clear_vec_high(s, rd);
}
}
}
/* Common vector code for handling integer to FP conversion */
static void handle_simd_intfp_conv(DisasContext *s, int rd, int rn,
int elements, int is_signed,
@ -6165,7 +6281,15 @@ static void disas_simd_scalar_shift_imm(DisasContext *s, uint32_t insn)
immh, immb, opcode, rn, rd);
break;
case 0xc: /* SQSHLU */
if (!is_u) {
unallocated_encoding(s);
return;
}
handle_simd_qshl(s, true, false, false, true, immh, immb, rn, rd);
break;
case 0xe: /* SQSHL, UQSHL */
handle_simd_qshl(s, true, false, is_u, is_u, immh, immb, rn, rd);
break;
case 0x1f: /* FCVTZS, FCVTZU */
unsupported_encoding(s, insn);
break;
@ -7409,7 +7533,15 @@ static void disas_simd_shift_imm(DisasContext *s, uint32_t insn)
opcode, rn, rd);
break;
case 0xc: /* SQSHLU */
if (!is_u) {
unallocated_encoding(s);
return;
}
handle_simd_qshl(s, false, is_q, false, true, immh, immb, rn, rd);
break;
case 0xe: /* SQSHL, UQSHL */
handle_simd_qshl(s, false, is_q, is_u, is_u, immh, immb, rn, rd);
break;
case 0x1f: /* FCVTZS/ FCVTZU */
unsupported_encoding(s, insn);
return;