On Fri, 2023-03-31 at 09:20 -0300, Arnaldo Carvalho de Melo wrote:
> Em Fri, Mar 31, 2023 at 09:14:39AM -0300, Arnaldo Carvalho de Melo escreveu:
> > > This part I didn't understand, do you see any possibility of a
> > > DW_TAG_LLVM_annotation pointing to another DW_TAG_LLVM_annotation?
> >
> > I _think_ its a noop, so will test your patch as-is, thanks!
>
> Tested, now we're left with normalizing base type names generated by
> clang and gcc, things like:
>
> --- /tmp/gcc 2023-03-31 09:16:34.100006650 -0300
> +++ /tmp/clang 2023-03-31 09:16:26.211789489 -0300
> @@ -96,8 +96,8 @@
>
> /* XXX 4 bytes hole, try to pack */
>
> - long unsigned int state; /* 216 8 */
> - long unsigned int state2; /* 224 8 */
> + unsigned long state; /* 216 8 */
> + unsigned long state2; /* 224 8 */
> struct Qdisc * next_sched; /* 232 8 */
> struct sk_buff_head skb_bad_txq; /* 240 24 */
>
> @@ -112,7 +112,7 @@
> /* XXX 40 bytes hole, try to pack */
>
> /* --- cacheline 6 boundary (384 bytes) --- */
> - long int privdata[]; /* 384 0 */
> + long privdata[]; /* 384 0 */
>
> /* size: 384, cachelines: 6, members: 28 */
> /* sum members: 260, holes: 4, sum holes: 124 */
> @@ -145,19 +145,19 @@
> /* XXX 4 bytes hole, try to pack */
>
> struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *); /* 8 8 */
> - int (*graft)(struct Qdisc *, long unsigned int, struct Qdisc *, struct Qdisc * *, struct netlink_ext_ack *); /* 16 8 */
> + int (*graft)(struct Qdisc *, unsigned long, struct Qdisc *, struct Qdisc * *, struct netlink_ext_ack *); /* 16 8 */
> - struct Qdisc * (*leaf)(struct Qdisc *, long unsigned int); /* 24 8 */
> + struct Qdisc * (*leaf)(struct Qdisc *, unsigned long); /* 24 8 */
> - void (*qlen_notify)(struct Qdisc *, long unsigned int); /* 32 8 */
> + void (*qlen_notify)(struct Qdisc *, unsigned long); /* 32 8 */
> - long unsigned int (*find)(struct Qdisc *, u32); /* 40 8 */
> + unsigned long (*find)(struct Qdisc *, u32); /* 40 8 */
> - int (*change)(struct Qdisc *, u32, u32, struct nlattr * *, long unsigned int *, struct netlink_ext_ack *); /* 48 8 */
> + int (*change)(struct Qdisc *, u32, u32, struct nlattr * *, unsigned long *, struct netlink_ext_ack *); /* 48 8 */
> - int (*delete)(struct Qdisc *, long unsigned int, struct netlink_ext_ack *); /* 56 8 */
> + int (*delete)(struct Qdisc *, unsigned long, struct netlink_ext_ack *); /* 56 8 */
> /* --- cacheline 1 boundary (64 bytes) --- */
> void (*walk)(struct Qdisc *, struct qdisc_walker *); /* 64 8 */
> - struct tcf_block * (*tcf_block)(struct Qdisc *, long unsigned int, struct netlink_ext_ack *); /* 72 8 */
> + struct tcf_block * (*tcf_block)(struct Qdisc *, unsigned long, struct netlink_ext_ack *); /* 72 8 */
> - long unsigned int (*bind_tcf)(struct Qdisc *, long unsigned int, u32); /* 80 8 */
> + unsigned long (*bind_tcf)(struct Qdisc *, unsigned long, u32); /* 80 8 */
> - void (*unbind_tcf)(struct Qdisc *, long unsigned int); /* 88 8 */
> + void (*unbind_tcf)(struct Qdisc *, unsigned long); /* 88 8 */
> - int (*dump)(struct Qdisc *, long unsigned int, struct sk_buff *, struct tcmsg *); /* 96 8 */
> + int (*dump)(struct Qdisc *, unsigned long, struct sk_buff *, struct tcmsg *); /* 96 8 */
> - int (*dump_stats)(struct Qdisc *, long unsigned int, struct gnet_dump *); /* 104 8 */
> + int (*dump_stats)(struct Qdisc *, unsigned long, struct gnet_dump *); /* 104 8 */
>
> /* size: 112, cachelines: 2, members: 14 */
> /* sum members: 108, holes: 1, sum holes: 4 */
> @@ -227,21 +227,21 @@
>
> This was affected somehow by these LLVM_annotation patches, I'll try to
> handle this later.
Are you sure it is related to LLVM_annotation patches?
I tried (4d17096 "btf_encoder: Compare functions via prototypes not parameter names")
and see the same behavior.
Looking at the DWARF, itself gcc and clang use different names for these types:
gcc:
0x0000002b: DW_TAG_base_type
DW_AT_byte_size (0x08)
DW_AT_encoding (DW_ATE_unsigned)
DW_AT_name ("long unsigned int")
clang:
0x000000f7: DW_TAG_base_type
DW_AT_name ("unsigned long")
DW_AT_encoding (DW_ATE_unsigned)
DW_AT_byte_size (0x08)
And the base type names are copied to BTF as is. Looks like some
normalization is necessary either in dwarf_loader.c:base_type__new()
or in fprintf.
Thanks,
Eduard
