On 12/22/23 00:43, Paolo Bonzini wrote:
Signed-off-by: Paolo Bonzini <[email protected]> --- tcg/i386/tcg-target.c.inc | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)diff --git a/tcg/i386/tcg-target.c.inc b/tcg/i386/tcg-target.c.inc index a83f8aab304..4e9f372d4fd 100644 --- a/tcg/i386/tcg-target.c.inc +++ b/tcg/i386/tcg-target.c.inc @@ -1332,7 +1332,11 @@ static void tgen_arithi(TCGContext *s, int c, int r0, return; }- if (c == ARITH_AND) {+ if ((c == ARITH_ADD || c == ARITH_SUB) && val == 128) { + /* Facilitate using an 8-bit immediate. */ + c ^= ARITH_ADD ^ ARITH_SUB; + val = -128; + } else if (c == ARITH_AND) { if (TCG_TARGET_REG_BITS == 64) { if (val == 0xffffffffu) { tcg_out_ext32u(s, r0, r0);
Need to check for !cf, because this swaps the sense of carry. Ought to merge this with the inc/dec block above to save comparisons. r~
