haraldwolff/qemu-patch-raspberry4
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity
qemu-patch-raspberry4/target/riscv/insn_trans/trans_rvb.c.inc
Philipp Tomsich 54c1760937 target/riscv: Fix orc.b implementation 
The earlier implementation fell into a corner case for bytes that were
0x01, giving a wrong result (but not affecting our application test
cases for strings, as an ASCII value 0x01 is rare in those...).

This changes the algorithm to:
 1. Mask out the high-bit of each bytes (so that each byte is <= 127).
 2. Add 127 to each byte (i.e. if the low 7 bits are not 0, this will overflow
    into the highest bit of each byte).
 3. Bitwise-or the original value back in (to cover those cases where the
    source byte was exactly 128) to saturate the high-bit.
 4. Shift-and-mask (implemented as a mask-and-shift) to extract the MSB of
    each byte into its LSB.
 5. Multiply with 0xff to fan out the LSB to all bits of each byte.

Fixes: d7a4fcb034 ("target/riscv: Add orc.b instruction for Zbb, removing gorc/gorci")

Signed-off-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
Reported-by: Vincent Palatin <vpalatin@rivosinc.com>
Tested-by: Vincent Palatin <vpalatin@rivosinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20211013184125.2010897-1-philipp.tomsich@vrull.eu
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2021-10-22 07:47:51 +10:00

491 lines
13 KiB
C++
Raw Blame History

/*
* RISC-V translation routines for the Zb[abcs] Standard Extension.
*
* Copyright (c) 2020 Kito Cheng, kito.cheng@sifive.com
* Copyright (c) 2020 Frank Chang, frank.chang@sifive.com
* Copyright (c) 2021 Philipp Tomsich, philipp.tomsich@vrull.eu
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2 or later, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#define REQUIRE_ZBA(ctx) do { \
if (!RISCV_CPU(ctx->cs)->cfg.ext_zba) { \
return false; \
} \
} while (0)
#define REQUIRE_ZBB(ctx) do { \
if (!RISCV_CPU(ctx->cs)->cfg.ext_zbb) { \
return false; \
} \
} while (0)
#define REQUIRE_ZBC(ctx) do { \
if (!RISCV_CPU(ctx->cs)->cfg.ext_zbc) { \
return false; \
} \
} while (0)
#define REQUIRE_ZBS(ctx) do { \
if (!RISCV_CPU(ctx->cs)->cfg.ext_zbs) { \
return false; \
} \
} while (0)
static void gen_clz(TCGv ret, TCGv arg1)
{
tcg_gen_clzi_tl(ret, arg1, TARGET_LONG_BITS);
}
static bool trans_clz(DisasContext *ctx, arg_clz *a)
{
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_ZERO, gen_clz);
}
static void gen_ctz(TCGv ret, TCGv arg1)
{
tcg_gen_ctzi_tl(ret, arg1, TARGET_LONG_BITS);
}
static bool trans_ctz(DisasContext *ctx, arg_ctz *a)
{
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_ZERO, gen_ctz);
}
static bool trans_cpop(DisasContext *ctx, arg_cpop *a)
{
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_ZERO, tcg_gen_ctpop_tl);
}
static bool trans_andn(DisasContext *ctx, arg_andn *a)
{
REQUIRE_ZBB(ctx);
return gen_arith(ctx, a, EXT_NONE, tcg_gen_andc_tl);
}
static bool trans_orn(DisasContext *ctx, arg_orn *a)
{
REQUIRE_ZBB(ctx);
return gen_arith(ctx, a, EXT_NONE, tcg_gen_orc_tl);
}
static bool trans_xnor(DisasContext *ctx, arg_xnor *a)
{
REQUIRE_ZBB(ctx);
return gen_arith(ctx, a, EXT_NONE, tcg_gen_eqv_tl);
}
static bool trans_min(DisasContext *ctx, arg_min *a)
{
REQUIRE_ZBB(ctx);
return gen_arith(ctx, a, EXT_SIGN, tcg_gen_smin_tl);
}
static bool trans_max(DisasContext *ctx, arg_max *a)
{
REQUIRE_ZBB(ctx);
return gen_arith(ctx, a, EXT_SIGN, tcg_gen_smax_tl);
}
static bool trans_minu(DisasContext *ctx, arg_minu *a)
{
REQUIRE_ZBB(ctx);
return gen_arith(ctx, a, EXT_SIGN, tcg_gen_umin_tl);
}
static bool trans_maxu(DisasContext *ctx, arg_maxu *a)
{
REQUIRE_ZBB(ctx);
return gen_arith(ctx, a, EXT_SIGN, tcg_gen_umax_tl);
}
static bool trans_sext_b(DisasContext *ctx, arg_sext_b *a)
{
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext8s_tl);
}
static bool trans_sext_h(DisasContext *ctx, arg_sext_h *a)
{
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext16s_tl);
}
static void gen_sbop_mask(TCGv ret, TCGv shamt)
{
tcg_gen_movi_tl(ret, 1);
tcg_gen_shl_tl(ret, ret, shamt);
}
static void gen_bset(TCGv ret, TCGv arg1, TCGv shamt)
{
TCGv t = tcg_temp_new();
gen_sbop_mask(t, shamt);
tcg_gen_or_tl(ret, arg1, t);
tcg_temp_free(t);
}
static bool trans_bset(DisasContext *ctx, arg_bset *a)
{
REQUIRE_ZBS(ctx);
return gen_shift(ctx, a, EXT_NONE, gen_bset);
}
static bool trans_bseti(DisasContext *ctx, arg_bseti *a)
{
REQUIRE_ZBS(ctx);
return gen_shift_imm_tl(ctx, a, EXT_NONE, gen_bset);
}
static void gen_bclr(TCGv ret, TCGv arg1, TCGv shamt)
{
TCGv t = tcg_temp_new();
gen_sbop_mask(t, shamt);
tcg_gen_andc_tl(ret, arg1, t);
tcg_temp_free(t);
}
static bool trans_bclr(DisasContext *ctx, arg_bclr *a)
{
REQUIRE_ZBS(ctx);
return gen_shift(ctx, a, EXT_NONE, gen_bclr);
}
static bool trans_bclri(DisasContext *ctx, arg_bclri *a)
{
REQUIRE_ZBS(ctx);
return gen_shift_imm_tl(ctx, a, EXT_NONE, gen_bclr);
}
static void gen_binv(TCGv ret, TCGv arg1, TCGv shamt)
{
TCGv t = tcg_temp_new();
gen_sbop_mask(t, shamt);
tcg_gen_xor_tl(ret, arg1, t);
tcg_temp_free(t);
}
static bool trans_binv(DisasContext *ctx, arg_binv *a)
{
REQUIRE_ZBS(ctx);
return gen_shift(ctx, a, EXT_NONE, gen_binv);
}
static bool trans_binvi(DisasContext *ctx, arg_binvi *a)
{
REQUIRE_ZBS(ctx);
return gen_shift_imm_tl(ctx, a, EXT_NONE, gen_binv);
}
static void gen_bext(TCGv ret, TCGv arg1, TCGv shamt)
{
tcg_gen_shr_tl(ret, arg1, shamt);
tcg_gen_andi_tl(ret, ret, 1);
}
static bool trans_bext(DisasContext *ctx, arg_bext *a)
{
REQUIRE_ZBS(ctx);
return gen_shift(ctx, a, EXT_NONE, gen_bext);
}
static bool trans_bexti(DisasContext *ctx, arg_bexti *a)
{
REQUIRE_ZBS(ctx);
return gen_shift_imm_tl(ctx, a, EXT_NONE, gen_bext);
}
static bool trans_ror(DisasContext *ctx, arg_ror *a)
{
REQUIRE_ZBB(ctx);
return gen_shift(ctx, a, EXT_NONE, tcg_gen_rotr_tl);
}
static bool trans_rori(DisasContext *ctx, arg_rori *a)
{
REQUIRE_ZBB(ctx);
return gen_shift_imm_fn(ctx, a, EXT_NONE, tcg_gen_rotri_tl);
}
static bool trans_rol(DisasContext *ctx, arg_rol *a)
{
REQUIRE_ZBB(ctx);
return gen_shift(ctx, a, EXT_NONE, tcg_gen_rotl_tl);
}
static bool trans_rev8_32(DisasContext *ctx, arg_rev8_32 *a)
{
REQUIRE_32BIT(ctx);
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, tcg_gen_bswap_tl);
}
static bool trans_rev8_64(DisasContext *ctx, arg_rev8_64 *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, tcg_gen_bswap_tl);
}
static void gen_orc_b(TCGv ret, TCGv source1)
{
TCGv tmp = tcg_temp_new();
TCGv low7 = tcg_constant_tl(dup_const_tl(MO_8, 0x7f));
/* Set msb in each byte if the byte was non-zero. */
tcg_gen_and_tl(tmp, source1, low7);
tcg_gen_add_tl(tmp, tmp, low7);
tcg_gen_or_tl(tmp, tmp, source1);
/* Extract the msb to the lsb in each byte */
tcg_gen_andc_tl(tmp, tmp, low7);
tcg_gen_shri_tl(tmp, tmp, 7);
/* Replicate the lsb of each byte across the byte. */
tcg_gen_muli_tl(ret, tmp, 0xff);
tcg_temp_free(tmp);
}
static bool trans_orc_b(DisasContext *ctx, arg_orc_b *a)
{
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_ZERO, gen_orc_b);
}
#define GEN_SHADD(SHAMT) \
static void gen_sh##SHAMT##add(TCGv ret, TCGv arg1, TCGv arg2) \
{ \
TCGv t = tcg_temp_new(); \
\
tcg_gen_shli_tl(t, arg1, SHAMT); \
tcg_gen_add_tl(ret, t, arg2); \
\
tcg_temp_free(t); \
}
GEN_SHADD(1)
GEN_SHADD(2)
GEN_SHADD(3)
#define GEN_TRANS_SHADD(SHAMT) \
static bool trans_sh##SHAMT##add(DisasContext *ctx, arg_sh##SHAMT##add *a) \
{ \
REQUIRE_ZBA(ctx); \
return gen_arith(ctx, a, EXT_NONE, gen_sh##SHAMT##add); \
}
GEN_TRANS_SHADD(1)
GEN_TRANS_SHADD(2)
GEN_TRANS_SHADD(3)
static bool trans_zext_h_32(DisasContext *ctx, arg_zext_h_32 *a)
{
REQUIRE_32BIT(ctx);
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext16u_tl);
}
static bool trans_zext_h_64(DisasContext *ctx, arg_zext_h_64 *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, tcg_gen_ext16u_tl);
}
static void gen_clzw(TCGv ret, TCGv arg1)
{
TCGv t = tcg_temp_new();
tcg_gen_shli_tl(t, arg1, 32);
tcg_gen_clzi_tl(ret, t, 32);
tcg_temp_free(t);
}
static bool trans_clzw(DisasContext *ctx, arg_clzw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, gen_clzw);
}
static void gen_ctzw(TCGv ret, TCGv arg1)
{
tcg_gen_ori_tl(ret, arg1, (target_ulong)MAKE_64BIT_MASK(32, 32));
tcg_gen_ctzi_tl(ret, ret, 64);
}
static bool trans_ctzw(DisasContext *ctx, arg_ctzw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
return gen_unary(ctx, a, EXT_NONE, gen_ctzw);
}
static bool trans_cpopw(DisasContext *ctx, arg_cpopw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
ctx->w = true;
return gen_unary(ctx, a, EXT_ZERO, tcg_gen_ctpop_tl);
}
static void gen_rorw(TCGv ret, TCGv arg1, TCGv arg2)
{
TCGv_i32 t1 = tcg_temp_new_i32();
TCGv_i32 t2 = tcg_temp_new_i32();
/* truncate to 32-bits */
tcg_gen_trunc_tl_i32(t1, arg1);
tcg_gen_trunc_tl_i32(t2, arg2);
tcg_gen_rotr_i32(t1, t1, t2);
/* sign-extend 64-bits */
tcg_gen_ext_i32_tl(ret, t1);
tcg_temp_free_i32(t1);
tcg_temp_free_i32(t2);
}
static bool trans_rorw(DisasContext *ctx, arg_rorw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
ctx->w = true;
return gen_shift(ctx, a, EXT_NONE, gen_rorw);
}
static bool trans_roriw(DisasContext *ctx, arg_roriw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
ctx->w = true;
return gen_shift_imm_tl(ctx, a, EXT_NONE, gen_rorw);
}
static void gen_rolw(TCGv ret, TCGv arg1, TCGv arg2)
{
TCGv_i32 t1 = tcg_temp_new_i32();
TCGv_i32 t2 = tcg_temp_new_i32();
/* truncate to 32-bits */
tcg_gen_trunc_tl_i32(t1, arg1);
tcg_gen_trunc_tl_i32(t2, arg2);
tcg_gen_rotl_i32(t1, t1, t2);
/* sign-extend 64-bits */
tcg_gen_ext_i32_tl(ret, t1);
tcg_temp_free_i32(t1);
tcg_temp_free_i32(t2);
}
static bool trans_rolw(DisasContext *ctx, arg_rolw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBB(ctx);
ctx->w = true;
return gen_shift(ctx, a, EXT_NONE, gen_rolw);
}
#define GEN_SHADD_UW(SHAMT) \
static void gen_sh##SHAMT##add_uw(TCGv ret, TCGv arg1, TCGv arg2) \
{ \
TCGv t = tcg_temp_new(); \
\
tcg_gen_ext32u_tl(t, arg1); \
\
tcg_gen_shli_tl(t, t, SHAMT); \
tcg_gen_add_tl(ret, t, arg2); \
\
tcg_temp_free(t); \
}
GEN_SHADD_UW(1)
GEN_SHADD_UW(2)
GEN_SHADD_UW(3)
#define GEN_TRANS_SHADD_UW(SHAMT) \
static bool trans_sh##SHAMT##add_uw(DisasContext *ctx, \
arg_sh##SHAMT##add_uw *a) \
{ \
REQUIRE_64BIT(ctx); \
REQUIRE_ZBA(ctx); \
return gen_arith(ctx, a, EXT_NONE, gen_sh##SHAMT##add_uw); \
}
GEN_TRANS_SHADD_UW(1)
GEN_TRANS_SHADD_UW(2)
GEN_TRANS_SHADD_UW(3)
static void gen_add_uw(TCGv ret, TCGv arg1, TCGv arg2)
{
TCGv t = tcg_temp_new();
tcg_gen_ext32u_tl(t, arg1);
tcg_gen_add_tl(ret, t, arg2);
tcg_temp_free(t);
}
static bool trans_add_uw(DisasContext *ctx, arg_add_uw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBA(ctx);
return gen_arith(ctx, a, EXT_NONE, gen_add_uw);
}
static void gen_slli_uw(TCGv dest, TCGv src, target_long shamt)
{
tcg_gen_deposit_z_tl(dest, src, shamt, MIN(32, TARGET_LONG_BITS - shamt));
}
static bool trans_slli_uw(DisasContext *ctx, arg_slli_uw *a)
{
REQUIRE_64BIT(ctx);
REQUIRE_ZBA(ctx);
return gen_shift_imm_fn(ctx, a, EXT_NONE, gen_slli_uw);
}
static bool trans_clmul(DisasContext *ctx, arg_clmul *a)
{
REQUIRE_ZBC(ctx);
return gen_arith(ctx, a, EXT_NONE, gen_helper_clmul);
}
static void gen_clmulh(TCGv dst, TCGv src1, TCGv src2)
{
gen_helper_clmulr(dst, src1, src2);
tcg_gen_shri_tl(dst, dst, 1);
}
static bool trans_clmulh(DisasContext *ctx, arg_clmulr *a)
{
REQUIRE_ZBC(ctx);
return gen_arith(ctx, a, EXT_NONE, gen_clmulh);
}
static bool trans_clmulr(DisasContext *ctx, arg_clmulh *a)
{
REQUIRE_ZBC(ctx);
return gen_arith(ctx, a, EXT_NONE, gen_helper_clmulr);
}
Reference in a new issue View git blame Copy permalink