From 8929906e212cbe606e361cbd32917dcbe5bb6dd0 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 16 Feb 2022 20:06:22 -0500 Subject: tcg: Remove dh_alias indirection for dh_typecode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The dh_alias redirect is intended to handle TCG types as distinguished from C types. TCG does not distinguish signed int from unsigned int, because they are the same size. However, we need to retain this distinction for dh_typecode, lest we fail to extend abi types properly for the host call parameters. This bug was detected when running the 'arm' emulator on an s390 system. The s390 uses TCG_TARGET_EXTEND_ARGS which triggers code in tcg_gen_callN to extend 32 bit values to 64 bits; the incorrect sign data in the typemask for each argument caused the values to be extended as unsigned values. This simple program exhibits the problem: static volatile int num = -9; static volatile int den = -5; int main(void) { int quo = num / den; printf("num %d den %d quo %d\n", num, den, quo); exit(0); } When run on the broken qemu, this results in: num -9 den -5 quo 0 The correct result is: num -9 den -5 quo 1 Fixes: 7319d83a735 ("tcg: Combine dh_is_64bit and dh_is_signed to dh_typecode") Resolves: https://gitlab.com/qemu-project/qemu/-/issues/876 Reviewed-by: Alex Bennée Reported-by: Christian Ehrhardt Tested-by: Christian Ehrhardt Tested-by: Keith Packard Signed-off-by: Richard Henderson --- include/exec/helper-head.h | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) (limited to 'include/exec') diff --git a/include/exec/helper-head.h b/include/exec/helper-head.h index b974eb394a..734af067fe 100644 --- a/include/exec/helper-head.h +++ b/include/exec/helper-head.h @@ -53,13 +53,16 @@ # ifdef TARGET_LONG_BITS # if TARGET_LONG_BITS == 32 # define dh_alias_tl i32 +# define dh_typecode_tl dh_typecode_i32 # else # define dh_alias_tl i64 +# define dh_typecode_tl dh_typecode_i64 # endif # endif -# define dh_alias_env ptr # define dh_ctype_tl target_ulong +# define dh_alias_env ptr # define dh_ctype_env CPUArchState * +# define dh_typecode_env dh_typecode_ptr #endif /* We can't use glue() here because it falls foul of C preprocessor @@ -92,18 +95,16 @@ #define dh_typecode_i64 4 #define dh_typecode_s64 5 #define dh_typecode_ptr 6 -#define dh_typecode(t) glue(dh_typecode_, dh_alias(t)) +#define dh_typecode_int dh_typecode_s32 +#define dh_typecode_f16 dh_typecode_i32 +#define dh_typecode_f32 dh_typecode_i32 +#define dh_typecode_f64 dh_typecode_i64 +#define dh_typecode_cptr dh_typecode_ptr +#define dh_typecode(t) dh_typecode_##t #define dh_callflag_i32 0 -#define dh_callflag_s32 0 -#define dh_callflag_int 0 #define dh_callflag_i64 0 -#define dh_callflag_s64 0 -#define dh_callflag_f16 0 -#define dh_callflag_f32 0 -#define dh_callflag_f64 0 #define dh_callflag_ptr 0 -#define dh_callflag_cptr dh_callflag_ptr #define dh_callflag_void 0 #define dh_callflag_noreturn TCG_CALL_NO_RETURN #define dh_callflag(t) glue(dh_callflag_, dh_alias(t)) -- cgit 1.4.1