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target/arm: Split gen_nop_hint

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Now that all callers pass a constant value, split the switch
statement into the individual trans_* functions.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190904193059.26202-61-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Richard Henderson 2019-09-04 12:30:50 -07:00 committed by Peter Maydell
parent 56e6250ede
commit 279de61a21
1 changed files with 24 additions and 43 deletions
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67
target/arm/translate.c
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@ -3061,46 +3061,6 @@ static void gen_exception_return(DisasContext *s, TCGv_i32 pc)
gen_rfe(s, pc, load_cpu_field(spsr));
}
/*
* For WFI we will halt the vCPU until an IRQ. For WFE and YIELD we
* only call the helper when running single threaded TCG code to ensure
* the next round-robin scheduled vCPU gets a crack. In MTTCG mode we
* just skip this instruction. Currently the SEV/SEVL instructions
* which are *one* of many ways to wake the CPU from WFE are not
* implemented so we can't sleep like WFI does.
*/
static void gen_nop_hint(DisasContext *s, int val)
{
switch (val) {
/* When running in MTTCG we don't generate jumps to the yield and
* WFE helpers as it won't affect the scheduling of other vCPUs.
* If we wanted to more completely model WFE/SEV so we don't busy
* spin unnecessarily we would need to do something more involved.
*/
case 1: /* yield */
if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
gen_set_pc_im(s, s->base.pc_next);
s->base.is_jmp = DISAS_YIELD;
}
break;
case 3: /* wfi */
gen_set_pc_im(s, s->base.pc_next);
s->base.is_jmp = DISAS_WFI;
break;
case 2: /* wfe */
if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
gen_set_pc_im(s, s->base.pc_next);
s->base.is_jmp = DISAS_WFE;
}
break;
case 4: /* sev */
case 5: /* sevl */
/* TODO: Implement SEV, SEVL and WFE. May help SMP performance. */
default: /* nop */
break;
}
}
#define CPU_V001 cpu_V0, cpu_V0, cpu_V1
static inline void gen_neon_add(int size, TCGv_i32 t0, TCGv_i32 t1)
@ -8194,19 +8154,40 @@ DO_SMLAWX(SMLAWT, 1, 1)
static bool trans_YIELD(DisasContext *s, arg_YIELD *a)
{
gen_nop_hint(s, 1);
/*
* When running single-threaded TCG code, use the helper to ensure that
* the next round-robin scheduled vCPU gets a crack. When running in
* MTTCG we don't generate jumps to the helper as it won't affect the
* scheduling of other vCPUs.
*/
if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
gen_set_pc_im(s, s->base.pc_next);
s->base.is_jmp = DISAS_YIELD;
}
return true;
}
static bool trans_WFE(DisasContext *s, arg_WFE *a)
{
gen_nop_hint(s, 2);
/*
* When running single-threaded TCG code, use the helper to ensure that
* the next round-robin scheduled vCPU gets a crack. In MTTCG mode we
* just skip this instruction. Currently the SEV/SEVL instructions,
* which are *one* of many ways to wake the CPU from WFE, are not
* implemented so we can't sleep like WFI does.
*/
if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
gen_set_pc_im(s, s->base.pc_next);
s->base.is_jmp = DISAS_WFE;
}
return true;
}
static bool trans_WFI(DisasContext *s, arg_WFI *a)
{
gen_nop_hint(s, 3);
/* For WFI, halt the vCPU until an IRQ. */
gen_set_pc_im(s, s->base.pc_next);
s->base.is_jmp = DISAS_WFI;
return true;
}