On 01/26/2011 08:50 AM, Alexander Graf wrote:
> Oh, you mean basically to have the following:
>
> TCGv_i32 regs32[16];
> TCGv_i64 regs[16];
>
> Then declare both as globals with offset and just switch between the
> access type using a disas struct variable. Once the TB ends, I'd
> obviously have to sync back to 64 bit again.
Maybe? I don't think that regs32 can overlap with regs in the real
cpu structure. Otherwise you have the same sort of sync problems as
was originally rejected.
I had been picturing regs32 as a member of DisasContext, and it would
hold tcg_temp_new_i32 variables as-needed. Something like
#if TCG_TARGET_REG_BITS == 64
static void writeback_reg32(DisasContext *dc, int r)
{
// ??? This macro should really exist to match TCGV_UNUSED_I32 etc.
if (!TCGV_IS_UNUSED_I32 (dc->regs32[r])) {
tcg_gen_deposit_tl(cpu_regs[r], cpu_regs[r],
MAKE_TCGV_I64 (GET_TCGV_I32 (dc->regs32[r])),
0, 32);
}
}
static void writeback_all_reg32(DisasContext *dc)
{
int i;
for (i = 0; i < 16; ++i) {
flush_reg32(dc, i);
}
}
static void flush_all_reg32(DisasContext *dc)
{
int i;
for (i = 0; i < 16; ++i) {
if (!TCGV_IS_UNUSED_I32 (dc->regs32[r])) {
tcg_temp_free_i32 (dc->regs32[r]);
TCGV_UNUSED_I32 (dc->regs32[r]);
}
}
}
static TCGv_i32 get_reg32(DisasContext *dc, int r)
{
if (TCGV_IS_UNUSED_I32 (dc->regs32[r])) {
dc->regs32[r] = tcg_temp_new_i32();
tcg_gen_trunc_i64_i32(dc->regs32[r], cpu_regs[r]);
}
return dc->regs32[r];
}
static TCGv_i64 get_reg64(DisasContext *dc, int r)
{
writeback_reg32(dc, r);
return cpu_regs[r];
}
#elif TCG_TARGET_REG_BITS == 32
static void writeback_reg32(DisasContext *dc, int r) { }
static void writeback_all_reg32(DisasContext *dc) { }
static void flush_all_reg32(DisasContext *dc) { }
static TCGv_i32 get_reg32(DisasContext *dc, int r)
{
return TCGV_LOW(cpu_regs[r]);
}
static TCGv_i64 get_reg64(DisasContext *dc, int r)
{
return cpu_regs[r];
}
#endif
r~
