From 22063f03a7626c77d7a4546b90fd27badd504269 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sun, 15 Dec 2024 10:06:12 +0100 Subject: [PATCH] target/i386: avoid using s->tmp0 for add to implicit registers For updates to implicit registers (RCX in LOOP instructions, RSI or RDI in string instructions, or the stack pointer) do the add directly using the registers (with no temporary) if 32-bit or 64-bit, or use a temporary created for the occasion if 16-bit. This is more efficient and removes move instructions for the MO_TL case. Signed-off-by: Paolo Bonzini Reviewed-by: Richard Henderson Link: https://lore.kernel.org/r/20241215090613.89588-14-pbonzini@redhat.com Signed-off-by: Paolo Bonzini --- target/i386/tcg/translate.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c index 9b2fde5eb2..a8935f487a 100644 --- a/target/i386/tcg/translate.c +++ b/target/i386/tcg/translate.c @@ -505,17 +505,24 @@ static inline void gen_op_jmp_v(DisasContext *s, TCGv dest) s->pc_save = -1; } -static inline -void gen_op_add_reg_im(DisasContext *s, MemOp size, int reg, int32_t val) +static inline void gen_op_add_reg(DisasContext *s, MemOp size, int reg, TCGv val) { - tcg_gen_addi_tl(s->tmp0, cpu_regs[reg], val); - gen_op_mov_reg_v(s, size, reg, s->tmp0); + /* Using cpu_regs[reg] does not work for xH registers. */ + assert(size >= MO_16); + if (size == MO_16) { + TCGv temp = tcg_temp_new(); + tcg_gen_add_tl(temp, cpu_regs[reg], val); + gen_op_mov_reg_v(s, size, reg, temp); + } else { + tcg_gen_add_tl(cpu_regs[reg], cpu_regs[reg], val); + tcg_gen_ext_tl(cpu_regs[reg], cpu_regs[reg], size); + } } -static inline void gen_op_add_reg(DisasContext *s, MemOp size, int reg, TCGv val) +static inline +void gen_op_add_reg_im(DisasContext *s, MemOp size, int reg, int32_t val) { - tcg_gen_add_tl(s->tmp0, cpu_regs[reg], val); - gen_op_mov_reg_v(s, size, reg, s->tmp0); + gen_op_add_reg(s, size, reg, tcg_constant_tl(val)); } static inline void gen_op_ld_v(DisasContext *s, int idx, TCGv t0, TCGv a0) -- 2.30.2