| Message ID | 20210601150106.12761-10-richard.henderson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | TCI fixes and cleanups | expand |
On 6/1/21 5:00 PM, Richard Henderson wrote: > The current setting is much too pessimistic. Indicating only > the one or two registers that are actually assigned after a > call should avoid unnecessary movement between the register > array and the stack array. > > Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org> > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > tcg/tci/tcg-target.c.inc | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
diff --git a/tcg/tci/tcg-target.c.inc b/tcg/tci/tcg-target.c.inc index ee6cdfec71..fb7c927fdf 100644 --- a/tcg/tci/tcg-target.c.inc +++ b/tcg/tci/tcg-target.c.inc @@ -812,8 +812,14 @@ static void tcg_target_init(TCGContext *s) tcg_target_available_regs[TCG_TYPE_I32] = BIT(TCG_TARGET_NB_REGS) - 1; /* Registers available for 64 bit operations. */ tcg_target_available_regs[TCG_TYPE_I64] = BIT(TCG_TARGET_NB_REGS) - 1; - /* TODO: Which registers should be set here? */ - tcg_target_call_clobber_regs = BIT(TCG_TARGET_NB_REGS) - 1; + /* + * The interpreter "registers" are in the local stack frame and + * cannot be clobbered by the called helper functions. However, + * the interpreter assumes a 64-bit return value and assigns to + * the return value registers. + */ + tcg_target_call_clobber_regs = + MAKE_64BIT_MASK(TCG_REG_R0, 64 / TCG_TARGET_REG_BITS); s->reserved_regs = 0; tcg_regset_set_reg(s->reserved_regs, TCG_REG_CALL_STACK);