diff options
author | Richard Henderson <richard.henderson@linaro.org> | 2020-12-14 16:13:55 -0600 |
---|---|---|
committer | Cornelia Huck <cohuck@redhat.com> | 2020-12-21 18:11:33 +0100 |
commit | a2db06da7dff662159c809059cda5e2aa302ec86 (patch) | |
tree | ca594af1e916b3496fb5f8c276fae0e2687c5c4e /target | |
parent | 3bcc3fa79902d72ab6385bb135e4c3e34931a697 (diff) | |
download | qemu-a2db06da7dff662159c809059cda5e2aa302ec86.zip qemu-a2db06da7dff662159c809059cda5e2aa302ec86.tar.gz qemu-a2db06da7dff662159c809059cda5e2aa302ec86.tar.bz2 |
target/s390x: Improve cc computation for SUBTRACT LOGICAL
The resulting cc is only dependent on the result and the carry-out.
Carry-out and borrow-out are inverses, so are trivially converted.
With tcg ops, it is easier to compute borrow-out than carry-out, so
save result and borrow-out rather than the inputs.
Borrow-out for 64-bit inputs is had via tcg_gen_sub2_i64 directly
into cc_src. Borrow-out for 32-bit inputs is had via extraction
from a normal 64-bit sub (with zero-extended inputs).
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20201214221356.68039-4-richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Diffstat (limited to 'target')
-rw-r--r-- | target/s390x/cc_helper.c | 40 | ||||
-rw-r--r-- | target/s390x/helper.c | 3 | ||||
-rw-r--r-- | target/s390x/insn-data.def | 24 | ||||
-rw-r--r-- | target/s390x/internal.h | 3 | ||||
-rw-r--r-- | target/s390x/translate.c | 55 |
5 files changed, 43 insertions, 82 deletions
diff --git a/target/s390x/cc_helper.c b/target/s390x/cc_helper.c index cd2c5c4..c7728d1 100644 --- a/target/s390x/cc_helper.c +++ b/target/s390x/cc_helper.c @@ -129,6 +129,11 @@ static uint32_t cc_calc_addu(uint64_t carry_out, uint64_t result) return (result != 0) + 2 * carry_out; } +static uint32_t cc_calc_subu(uint64_t borrow_out, uint64_t result) +{ + return cc_calc_addu(borrow_out + 1, result); +} + static uint32_t cc_calc_add_64(int64_t a1, int64_t a2, int64_t ar) { if ((a1 > 0 && a2 > 0 && ar < 0) || (a1 < 0 && a2 < 0 && ar > 0)) { @@ -159,19 +164,6 @@ static uint32_t cc_calc_sub_64(int64_t a1, int64_t a2, int64_t ar) } } -static uint32_t cc_calc_subu_64(uint64_t a1, uint64_t a2, uint64_t ar) -{ - if (ar == 0) { - return 2; - } else { - if (a2 > a1) { - return 1; - } else { - return 3; - } - } -} - static uint32_t cc_calc_subb_64(uint64_t a1, uint64_t a2, uint64_t ar) { int borrow_out; @@ -245,19 +237,6 @@ static uint32_t cc_calc_sub_32(int32_t a1, int32_t a2, int32_t ar) } } -static uint32_t cc_calc_subu_32(uint32_t a1, uint32_t a2, uint32_t ar) -{ - if (ar == 0) { - return 2; - } else { - if (a2 > a1) { - return 1; - } else { - return 3; - } - } -} - static uint32_t cc_calc_subb_32(uint32_t a1, uint32_t a2, uint32_t ar) { int borrow_out; @@ -462,15 +441,15 @@ static uint32_t do_calc_cc(CPUS390XState *env, uint32_t cc_op, case CC_OP_ADDU: r = cc_calc_addu(src, dst); break; + case CC_OP_SUBU: + r = cc_calc_subu(src, dst); + break; case CC_OP_ADD_64: r = cc_calc_add_64(src, dst, vr); break; case CC_OP_SUB_64: r = cc_calc_sub_64(src, dst, vr); break; - case CC_OP_SUBU_64: - r = cc_calc_subu_64(src, dst, vr); - break; case CC_OP_SUBB_64: r = cc_calc_subb_64(src, dst, vr); break; @@ -493,9 +472,6 @@ static uint32_t do_calc_cc(CPUS390XState *env, uint32_t cc_op, case CC_OP_SUB_32: r = cc_calc_sub_32(src, dst, vr); break; - case CC_OP_SUBU_32: - r = cc_calc_subu_32(src, dst, vr); - break; case CC_OP_SUBB_32: r = cc_calc_subb_32(src, dst, vr); break; diff --git a/target/s390x/helper.c b/target/s390x/helper.c index 4f4561b..fa3aa50 100644 --- a/target/s390x/helper.c +++ b/target/s390x/helper.c @@ -396,6 +396,7 @@ const char *cc_name(enum cc_op cc_op) [CC_OP_STATIC] = "CC_OP_STATIC", [CC_OP_NZ] = "CC_OP_NZ", [CC_OP_ADDU] = "CC_OP_ADDU", + [CC_OP_SUBU] = "CC_OP_SUBU", [CC_OP_LTGT_32] = "CC_OP_LTGT_32", [CC_OP_LTGT_64] = "CC_OP_LTGT_64", [CC_OP_LTUGTU_32] = "CC_OP_LTUGTU_32", @@ -404,13 +405,11 @@ const char *cc_name(enum cc_op cc_op) [CC_OP_LTGT0_64] = "CC_OP_LTGT0_64", [CC_OP_ADD_64] = "CC_OP_ADD_64", [CC_OP_SUB_64] = "CC_OP_SUB_64", - [CC_OP_SUBU_64] = "CC_OP_SUBU_64", [CC_OP_SUBB_64] = "CC_OP_SUBB_64", [CC_OP_ABS_64] = "CC_OP_ABS_64", [CC_OP_NABS_64] = "CC_OP_NABS_64", [CC_OP_ADD_32] = "CC_OP_ADD_32", [CC_OP_SUB_32] = "CC_OP_SUB_32", - [CC_OP_SUBU_32] = "CC_OP_SUBU_32", [CC_OP_SUBB_32] = "CC_OP_SUBB_32", [CC_OP_ABS_32] = "CC_OP_ABS_32", [CC_OP_NABS_32] = "CC_OP_NABS_32", diff --git a/target/s390x/insn-data.def b/target/s390x/insn-data.def index e380723..7ff3e7e 100644 --- a/target/s390x/insn-data.def +++ b/target/s390x/insn-data.def @@ -900,21 +900,21 @@ C(0xb9c9, SHHHR, RRF_a, HW, r2_sr32, r3_sr32, new, r1_32h, sub, subs32) C(0xb9d9, SHHLR, RRF_a, HW, r2_sr32, r3, new, r1_32h, sub, subs32) /* SUBTRACT LOGICAL */ - C(0x1f00, SLR, RR_a, Z, r1, r2, new, r1_32, sub, subu32) - C(0xb9fb, SLRK, RRF_a, DO, r2, r3, new, r1_32, sub, subu32) - C(0x5f00, SL, RX_a, Z, r1, m2_32u, new, r1_32, sub, subu32) - C(0xe35f, SLY, RXY_a, LD, r1, m2_32u, new, r1_32, sub, subu32) - C(0xb90b, SLGR, RRE, Z, r1, r2, r1, 0, sub, subu64) - C(0xb91b, SLGFR, RRE, Z, r1, r2_32u, r1, 0, sub, subu64) - C(0xb9eb, SLGRK, RRF_a, DO, r2, r3, r1, 0, sub, subu64) - C(0xe30b, SLG, RXY_a, Z, r1, m2_64, r1, 0, sub, subu64) - C(0xe31b, SLGF, RXY_a, Z, r1, m2_32u, r1, 0, sub, subu64) + C(0x1f00, SLR, RR_a, Z, r1_32u, r2_32u, new, r1_32, sub, subu32) + C(0xb9fb, SLRK, RRF_a, DO, r2_32u, r3_32u, new, r1_32, sub, subu32) + C(0x5f00, SL, RX_a, Z, r1_32u, m2_32u, new, r1_32, sub, subu32) + C(0xe35f, SLY, RXY_a, LD, r1_32u, m2_32u, new, r1_32, sub, subu32) + C(0xb90b, SLGR, RRE, Z, r1, r2, r1, 0, subu64, subu64) + C(0xb91b, SLGFR, RRE, Z, r1, r2_32u, r1, 0, subu64, subu64) + C(0xb9eb, SLGRK, RRF_a, DO, r2, r3, r1, 0, subu64, subu64) + C(0xe30b, SLG, RXY_a, Z, r1, m2_64, r1, 0, subu64, subu64) + C(0xe31b, SLGF, RXY_a, Z, r1, m2_32u, r1, 0, subu64, subu64) /* SUBTRACT LOCICAL HIGH */ C(0xb9cb, SLHHHR, RRF_a, HW, r2_sr32, r3_sr32, new, r1_32h, sub, subu32) - C(0xb9db, SLHHLR, RRF_a, HW, r2_sr32, r3, new, r1_32h, sub, subu32) + C(0xb9db, SLHHLR, RRF_a, HW, r2_sr32, r3_32u, new, r1_32h, sub, subu32) /* SUBTRACT LOGICAL IMMEDIATE */ - C(0xc205, SLFI, RIL_a, EI, r1, i2_32u, new, r1_32, sub, subu32) - C(0xc204, SLGFI, RIL_a, EI, r1, i2_32u, r1, 0, sub, subu64) + C(0xc205, SLFI, RIL_a, EI, r1_32u, i2_32u, new, r1_32, sub, subu32) + C(0xc204, SLGFI, RIL_a, EI, r1, i2_32u, r1, 0, subu64, subu64) /* SUBTRACT LOGICAL WITH BORROW */ C(0xb999, SLBR, RRE, Z, r1, r2, new, r1_32, subb, subb32) C(0xb989, SLBGR, RRE, Z, r1, r2, r1, 0, subb, subb64) diff --git a/target/s390x/internal.h b/target/s390x/internal.h index f5f3ae0..4077047 100644 --- a/target/s390x/internal.h +++ b/target/s390x/internal.h @@ -161,6 +161,7 @@ enum cc_op { CC_OP_NZ, /* env->cc_dst != 0 */ CC_OP_ADDU, /* dst != 0, src = carry out (0,1) */ + CC_OP_SUBU, /* dst != 0, src = borrow out (0,-1) */ CC_OP_LTGT_32, /* signed less/greater than (32bit) */ CC_OP_LTGT_64, /* signed less/greater than (64bit) */ @@ -171,7 +172,6 @@ enum cc_op { CC_OP_ADD_64, /* overflow on add (64bit) */ CC_OP_SUB_64, /* overflow on subtraction (64bit) */ - CC_OP_SUBU_64, /* overflow on unsigned subtraction (64bit) */ CC_OP_SUBB_64, /* overflow on unsigned sub-borrow (64bit) */ CC_OP_ABS_64, /* sign eval on abs (64bit) */ CC_OP_NABS_64, /* sign eval on nabs (64bit) */ @@ -179,7 +179,6 @@ enum cc_op { CC_OP_ADD_32, /* overflow on add (32bit) */ CC_OP_SUB_32, /* overflow on subtraction (32bit) */ - CC_OP_SUBU_32, /* overflow on unsigned subtraction (32bit) */ CC_OP_SUBB_32, /* overflow on unsigned sub-borrow (32bit) */ CC_OP_ABS_32, /* sign eval on abs (64bit) */ CC_OP_NABS_32, /* sign eval on nabs (64bit) */ diff --git a/target/s390x/translate.c b/target/s390x/translate.c index d1d97e4..40add1d 100644 --- a/target/s390x/translate.c +++ b/target/s390x/translate.c @@ -601,11 +601,9 @@ static void gen_op_calc_cc(DisasContext *s) /* FALLTHRU */ case CC_OP_ADD_64: case CC_OP_SUB_64: - case CC_OP_SUBU_64: case CC_OP_SUBB_64: case CC_OP_ADD_32: case CC_OP_SUB_32: - case CC_OP_SUBU_32: case CC_OP_SUBB_32: local_cc_op = tcg_const_i32(s->cc_op); break; @@ -656,6 +654,7 @@ static void gen_op_calc_cc(DisasContext *s) case CC_OP_TM_64: case CC_OP_SLA_32: case CC_OP_SLA_64: + case CC_OP_SUBU: case CC_OP_NZ_F128: case CC_OP_VC: case CC_OP_MULS_64: @@ -664,11 +663,9 @@ static void gen_op_calc_cc(DisasContext *s) break; case CC_OP_ADD_64: case CC_OP_SUB_64: - case CC_OP_SUBU_64: case CC_OP_SUBB_64: case CC_OP_ADD_32: case CC_OP_SUB_32: - case CC_OP_SUBU_32: case CC_OP_SUBB_32: /* 3 arguments */ gen_helper_calc_cc(cc_op, cpu_env, local_cc_op, cc_src, cc_dst, cc_vr); @@ -843,6 +840,7 @@ static void disas_jcc(DisasContext *s, DisasCompare *c, uint32_t mask) break; case CC_OP_ADDU: + case CC_OP_SUBU: switch (mask) { case 8 | 2: /* result == 0 */ cond = TCG_COND_EQ; @@ -850,33 +848,11 @@ static void disas_jcc(DisasContext *s, DisasCompare *c, uint32_t mask) case 4 | 1: /* result != 0 */ cond = TCG_COND_NE; break; - case 8 | 4: /* no carry */ - cond = TCG_COND_EQ; + case 8 | 4: /* !carry (borrow) */ + cond = old_cc_op == CC_OP_ADDU ? TCG_COND_EQ : TCG_COND_NE; break; - case 2 | 1: /* carry */ - cond = TCG_COND_NE; - break; - default: - goto do_dynamic; - } - account_inline_branch(s, old_cc_op); - break; - - case CC_OP_SUBU_32: - case CC_OP_SUBU_64: - /* Note that CC=0 is impossible; treat it as dont-care. */ - switch (mask & 7) { - case 2: /* zero -> op1 == op2 */ - cond = TCG_COND_EQ; - break; - case 4 | 1: /* !zero -> op1 != op2 */ - cond = TCG_COND_NE; - break; - case 4: /* borrow (!carry) -> op1 < op2 */ - cond = TCG_COND_LTU; - break; - case 2 | 1: /* !borrow (carry) -> op1 >= op2 */ - cond = TCG_COND_GEU; + case 2 | 1: /* carry (!borrow) */ + cond = old_cc_op == CC_OP_ADDU ? TCG_COND_NE : TCG_COND_EQ; break; default: goto do_dynamic; @@ -911,7 +887,6 @@ static void disas_jcc(DisasContext *s, DisasCompare *c, uint32_t mask) break; case CC_OP_LTGT_32: case CC_OP_LTUGTU_32: - case CC_OP_SUBU_32: c->is_64 = false; c->u.s32.a = tcg_temp_new_i32(); tcg_gen_extrl_i64_i32(c->u.s32.a, cc_src); @@ -928,7 +903,6 @@ static void disas_jcc(DisasContext *s, DisasCompare *c, uint32_t mask) break; case CC_OP_LTGT_64: case CC_OP_LTUGTU_64: - case CC_OP_SUBU_64: c->u.s64.a = cc_src; c->u.s64.b = cc_dst; c->g1 = c->g2 = true; @@ -943,6 +917,7 @@ static void disas_jcc(DisasContext *s, DisasCompare *c, uint32_t mask) break; case CC_OP_ADDU: + case CC_OP_SUBU: c->is_64 = true; c->u.s64.b = tcg_const_i64(0); c->g1 = true; @@ -1446,6 +1421,9 @@ static void compute_carry(DisasContext *s) case CC_OP_ADDU: /* The carry value is already in cc_src (1,0). */ break; + case CC_OP_SUBU: + tcg_gen_addi_i64(cc_src, cc_src, 1); + break; default: gen_op_calc_cc(s); /* fall through */ @@ -4761,6 +4739,13 @@ static DisasJumpType op_sub(DisasContext *s, DisasOps *o) return DISAS_NEXT; } +static DisasJumpType op_subu64(DisasContext *s, DisasOps *o) +{ + tcg_gen_movi_i64(cc_src, 0); + tcg_gen_sub2_i64(o->out, cc_src, o->in1, cc_src, o->in2, cc_src); + return DISAS_NEXT; +} + static DisasJumpType op_subb(DisasContext *s, DisasOps *o) { DisasCompare cmp; @@ -5312,12 +5297,14 @@ static void cout_subs64(DisasContext *s, DisasOps *o) static void cout_subu32(DisasContext *s, DisasOps *o) { - gen_op_update3_cc_i64(s, CC_OP_SUBU_32, o->in1, o->in2, o->out); + tcg_gen_sari_i64(cc_src, o->out, 32); + tcg_gen_ext32u_i64(cc_dst, o->out); + gen_op_update2_cc_i64(s, CC_OP_SUBU, cc_src, cc_dst); } static void cout_subu64(DisasContext *s, DisasOps *o) { - gen_op_update3_cc_i64(s, CC_OP_SUBU_64, o->in1, o->in2, o->out); + gen_op_update2_cc_i64(s, CC_OP_SUBU, cc_src, o->out); } static void cout_subb32(DisasContext *s, DisasOps *o) |