diff options
author | Richard Henderson <richard.henderson@linaro.org> | 2023-01-19 06:46:16 -1000 |
---|---|---|
committer | Richard Henderson <richard.henderson@linaro.org> | 2023-01-23 14:39:48 -1000 |
commit | 6aa89be5c5ff9a534280b06fad9b01604e2155cb (patch) | |
tree | cf6ffa0ea9620d850652cc270c0541f34463f830 /include/exec | |
parent | 2466bb3b083f965ef1ec12368c07e7d1e2f0b4c4 (diff) |
tcg: Mark tcg helpers noinline to avoid an issue with LTO
Marking helpers __attribute__((noinline)) prevents an issue
with GCC's ipa-split pass under --enable-lto.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1454
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Idan Horowitz <idan.horowitz@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'include/exec')
-rw-r--r-- | include/exec/helper-proto.h | 32 |
1 files changed, 24 insertions, 8 deletions
diff --git a/include/exec/helper-proto.h b/include/exec/helper-proto.h index c4b1bda632..7a3f04b58c 100644 --- a/include/exec/helper-proto.h +++ b/include/exec/helper-proto.h @@ -6,34 +6,49 @@ #include "exec/helper-head.h" +/* + * Work around an issue with --enable-lto, in which GCC's ipa-split pass + * decides to split out the noreturn code paths that raise an exception, + * taking the __builtin_return_address() along into the new function, + * where it no longer computes a value that returns to TCG generated code. + * Despite the name, the noinline attribute affects splitter, so this + * prevents the optimization in question. Given that helpers should not + * otherwise be called directly, this should have any other visible effect. + * + * See https://gitlab.com/qemu-project/qemu/-/issues/1454 + */ +#define DEF_HELPER_ATTR __attribute__((noinline)) + #define DEF_HELPER_FLAGS_0(name, flags, ret) \ -dh_ctype(ret) HELPER(name) (void); +dh_ctype(ret) HELPER(name) (void) DEF_HELPER_ATTR; #define DEF_HELPER_FLAGS_1(name, flags, ret, t1) \ -dh_ctype(ret) HELPER(name) (dh_ctype(t1)); +dh_ctype(ret) HELPER(name) (dh_ctype(t1)) DEF_HELPER_ATTR; #define DEF_HELPER_FLAGS_2(name, flags, ret, t1, t2) \ -dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2)); +dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2)) DEF_HELPER_ATTR; #define DEF_HELPER_FLAGS_3(name, flags, ret, t1, t2, t3) \ -dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2), dh_ctype(t3)); +dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2), \ + dh_ctype(t3)) DEF_HELPER_ATTR; #define DEF_HELPER_FLAGS_4(name, flags, ret, t1, t2, t3, t4) \ dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2), dh_ctype(t3), \ - dh_ctype(t4)); + dh_ctype(t4)) DEF_HELPER_ATTR; #define DEF_HELPER_FLAGS_5(name, flags, ret, t1, t2, t3, t4, t5) \ dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2), dh_ctype(t3), \ - dh_ctype(t4), dh_ctype(t5)); + dh_ctype(t4), dh_ctype(t5)) DEF_HELPER_ATTR; #define DEF_HELPER_FLAGS_6(name, flags, ret, t1, t2, t3, t4, t5, t6) \ dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2), dh_ctype(t3), \ - dh_ctype(t4), dh_ctype(t5), dh_ctype(t6)); + dh_ctype(t4), dh_ctype(t5), \ + dh_ctype(t6)) DEF_HELPER_ATTR; #define DEF_HELPER_FLAGS_7(name, flags, ret, t1, t2, t3, t4, t5, t6, t7) \ dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2), dh_ctype(t3), \ dh_ctype(t4), dh_ctype(t5), dh_ctype(t6), \ - dh_ctype(t7)); + dh_ctype(t7)) DEF_HELPER_ATTR; #define IN_HELPER_PROTO @@ -51,5 +66,6 @@ dh_ctype(ret) HELPER(name) (dh_ctype(t1), dh_ctype(t2), dh_ctype(t3), \ #undef DEF_HELPER_FLAGS_5 #undef DEF_HELPER_FLAGS_6 #undef DEF_HELPER_FLAGS_7 +#undef DEF_HELPER_ATTR #endif /* HELPER_PROTO_H */ |