Since TCG_TYPE_I32 values are kept zero-extended in registers, via omission of the REXW bit, we need not extend if the register matches. This is already relied upon by qemu_{ld,st}.
Reviewed-by: Alex Bennée <alex.ben...@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org> Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- tcg/i386/tcg-target.c.inc | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tcg/i386/tcg-target.c.inc b/tcg/i386/tcg-target.c.inc index 647c31fa23..aed5bbd94c 100644 --- a/tcg/i386/tcg-target.c.inc +++ b/tcg/i386/tcg-target.c.inc @@ -1323,7 +1323,9 @@ static void tcg_out_exts_i32_i64(TCGContext *s, TCGReg dest, TCGReg src) static void tcg_out_extu_i32_i64(TCGContext *s, TCGReg dest, TCGReg src) { - tcg_out_ext32u(s, dest, src); + if (dest != src) { + tcg_out_ext32u(s, dest, src); + } } static void tcg_out_extrl_i64_i32(TCGContext *s, TCGReg dest, TCGReg src) -- 2.34.1