OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

target/xtensa: only rotate window in the retw helper

Browse Source 
Move return address calculation and WINDOW_START adjustment out of the
retw helper to simplify logic a bit and avoid using registers directly.
Pass a0 as a parameter to the helper.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov 2019-02-11 12:22:29 -08:00
parent 8df3fd3596
commit c949009bc0
3 changed files with 10 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
target/xtensa/helper.h
View File

@ -7,7 +7,7 @@ DEF_HELPER_1(sync_windowbase, void, env)
DEF_HELPER_4(entry, void, env, i32, i32, i32)
DEF_HELPER_2(test_ill_retw, void, env, i32)
DEF_HELPER_2(test_underflow_retw, void, env, i32)
DEF_HELPER_2(retw, i32, env, i32)
DEF_HELPER_2(retw, void, env, i32)
DEF_HELPER_3(window_check, noreturn, env, i32, i32)
DEF_HELPER_1(restore_owb, void, env)
DEF_HELPER_2(movsp, void, env, i32)

9
target/xtensa/translate.c
View File

@ -2227,8 +2227,13 @@ static bool test_ill_retw(DisasContext *dc, const uint32_t arg[],
static void translate_retw(DisasContext *dc, const uint32_t arg[],
const uint32_t par[])
{
TCGv_i32 tmp = tcg_const_i32(dc->pc);
gen_helper_retw(tmp, cpu_env, tmp);
TCGv_i32 tmp = tcg_const_i32(1);
tcg_gen_shl_i32(tmp, tmp, cpu_SR[WINDOW_BASE]);
tcg_gen_andc_i32(cpu_SR[WINDOW_START],
cpu_SR[WINDOW_START], tmp);
tcg_gen_movi_i32(tmp, dc->pc);
tcg_gen_deposit_i32(tmp, tmp, cpu_R[0], 0, 30);
gen_helper_retw(cpu_env, cpu_R[0]);
gen_jump(dc, tmp);
tcg_temp_free(tmp);
}

8
target/xtensa/win_helper.c
View File

@ -184,15 +184,11 @@ void HELPER(test_underflow_retw)(CPUXtensaState *env, uint32_t pc)
}
}
uint32_t HELPER(retw)(CPUXtensaState *env, uint32_t pc)
void HELPER(retw)(CPUXtensaState *env, uint32_t a0)
{
int n = (env->regs[0] >> 30) & 0x3;
uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env);
uint32_t ret_pc = (pc & 0xc0000000) | (env->regs[0] & 0x3fffffff);
int n = (a0 >> 30) & 0x3;
xtensa_rotate_window(env, -n);
env->sregs[WINDOW_START] &= ~windowstart_bit(windowbase, env);
return ret_pc;
}
void xtensa_restore_owb(CPUXtensaState *env)