target/ppc: Rework store conditional to avoid branch

Rework store conditional to avoid a branch in the success case.
Change some of the variable names and layout while here so
gen_conditional_store more closely matches gen_stqcx_.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20230605025445.161932-4-npiggin@gmail.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
This commit is contained in:
Nicholas Piggin 2023-06-05 12:54:45 +10:00 committed by Daniel Henrique Barboza
parent 2c901dca18
commit 21ee07e773

View File

@ -3697,31 +3697,32 @@ static void gen_stdat(DisasContext *ctx)
static void gen_conditional_store(DisasContext *ctx, MemOp memop)
{
TCGLabel *l1 = gen_new_label();
TCGLabel *l2 = gen_new_label();
TCGv t0 = tcg_temp_new();
int reg = rS(ctx->opcode);
gen_set_access_type(ctx, ACCESS_RES);
gen_addr_reg_index(ctx, t0);
tcg_gen_brcond_tl(TCG_COND_NE, t0, cpu_reserve, l1);
tcg_gen_brcondi_tl(TCG_COND_NE, cpu_reserve_length, memop_size(memop), l1);
TCGLabel *lfail;
TCGv EA;
TCGv cr0;
TCGv t0;
int rs = rS(ctx->opcode);
lfail = gen_new_label();
EA = tcg_temp_new();
cr0 = tcg_temp_new();
t0 = tcg_temp_new();
tcg_gen_mov_tl(cr0, cpu_so);
gen_set_access_type(ctx, ACCESS_RES);
gen_addr_reg_index(ctx, EA);
tcg_gen_brcond_tl(TCG_COND_NE, EA, cpu_reserve, lfail);
tcg_gen_brcondi_tl(TCG_COND_NE, cpu_reserve_length, memop_size(memop), lfail);
tcg_gen_atomic_cmpxchg_tl(t0, cpu_reserve, cpu_reserve_val,
cpu_gpr[reg], ctx->mem_idx,
cpu_gpr[rs], ctx->mem_idx,
DEF_MEMOP(memop) | MO_ALIGN);
tcg_gen_setcond_tl(TCG_COND_EQ, t0, t0, cpu_reserve_val);
tcg_gen_shli_tl(t0, t0, CRF_EQ_BIT);
tcg_gen_or_tl(t0, t0, cpu_so);
tcg_gen_trunc_tl_i32(cpu_crf[0], t0);
tcg_gen_br(l2);
tcg_gen_or_tl(cr0, cr0, t0);
gen_set_label(l1);
tcg_gen_trunc_tl_i32(cpu_crf[0], cpu_so);
gen_set_label(l2);
gen_set_label(lfail);
tcg_gen_trunc_tl_i32(cpu_crf[0], cr0);
tcg_gen_movi_tl(cpu_reserve, -1);
}
@ -3775,25 +3776,26 @@ static void gen_lqarx(DisasContext *ctx)
/* stqcx. */
static void gen_stqcx_(DisasContext *ctx)
{
TCGLabel *lab_fail, *lab_over;
int rs = rS(ctx->opcode);
TCGLabel *lfail;
TCGv EA, t0, t1;
TCGv cr0;
TCGv_i128 cmp, val;
int rs = rS(ctx->opcode);
if (unlikely(rs & 1)) {
gen_inval_exception(ctx, POWERPC_EXCP_INVAL_INVAL);
return;
}
lab_fail = gen_new_label();
lab_over = gen_new_label();
gen_set_access_type(ctx, ACCESS_RES);
lfail = gen_new_label();
EA = tcg_temp_new();
gen_addr_reg_index(ctx, EA);
cr0 = tcg_temp_new();
tcg_gen_brcond_tl(TCG_COND_NE, EA, cpu_reserve, lab_fail);
tcg_gen_brcondi_tl(TCG_COND_NE, cpu_reserve_length, 16, lab_fail);
tcg_gen_mov_tl(cr0, cpu_so);
gen_set_access_type(ctx, ACCESS_RES);
gen_addr_reg_index(ctx, EA);
tcg_gen_brcond_tl(TCG_COND_NE, EA, cpu_reserve, lfail);
tcg_gen_brcondi_tl(TCG_COND_NE, cpu_reserve_length, 16, lfail);
cmp = tcg_temp_new_i128();
val = tcg_temp_new_i128();
@ -3816,15 +3818,10 @@ static void gen_stqcx_(DisasContext *ctx)
tcg_gen_setcondi_tl(TCG_COND_EQ, t0, t0, 0);
tcg_gen_shli_tl(t0, t0, CRF_EQ_BIT);
tcg_gen_or_tl(t0, t0, cpu_so);
tcg_gen_trunc_tl_i32(cpu_crf[0], t0);
tcg_gen_or_tl(cr0, cr0, t0);
tcg_gen_br(lab_over);
gen_set_label(lab_fail);
tcg_gen_trunc_tl_i32(cpu_crf[0], cpu_so);
gen_set_label(lab_over);
gen_set_label(lfail);
tcg_gen_trunc_tl_i32(cpu_crf[0], cr0);
tcg_gen_movi_tl(cpu_reserve, -1);
}
#endif /* defined(TARGET_PPC64) */