dc1c43d726
Current BTF only supports 32-bit value. For example,
enum T { VAL = 0xffffFFFF00000008 };
the generated BTF looks like
.long 16 # BTF_KIND_ENUM(id = 4)
.long 100663297 # 0x6000001
.long 8
.long 18
.long 8
The encoded value is 8 which equals to (uint32_t)0xffffFFFF00000008
and this is incorrect.
This patch introduced BTF_KIND_ENUM64 which permits to encode
64-bit value. The format for each enumerator looks like:
.long name_offset
.long (uint32_t)value # lower-32 bit value
.long value >> 32 # high-32 bit value
We use two 32-bit values to represent a 64-bit value as current
BTF type subsection has 4-byte alignment and gaps are not permitted
in the subsection.
This patch also added support for kflag (the bit 31 of CommonType.Info)
such that kflag = 1 implies the value is signed and kflag = 0
implies the value is unsigned. The kernel UAPI enumerator definition is
struct btf_enum {
__u32 name_off;
__s32 val;
};
so kflag = 0 with unsigned value provides backward compatability.
With this patch, for
enum T { VAL = 0xffffFFFF00000008 };
the generated BTF looks like
.long 16 # BTF_KIND_ENUM64(id = 4)
.long 3187671053 # 0x13000001
.long 8
.long 18
.long 8 # 0x8
.long 4294967295 # 0xffffffff
and the enumerator value and signedness are encoded correctly.
Differential Revision: https://reviews.llvm.org/D124641
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| .. | ||
| align.ll | ||
| array-1d-char.ll | ||
| array-1d-int.ll | ||
| array-2d-int.ll | ||
| array-size-0.ll | ||
| array-typedef.ll | ||
| binary-format.ll | ||
| builtin-btf-type-id-2.ll | ||
| builtin-btf-type-id.ll | ||
| char-no-debuginfo.ll | ||
| char.ll | ||
| double.ll | ||
| empty-btf.ll | ||
| enum-basic.ll | ||
| extern-builtin.ll | ||
| extern-func-arg.ll | ||
| extern-func-ptr.ll | ||
| extern-global-var.ll | ||
| extern-var-func-weak-section.ll | ||
| extern-var-func-weak.ll | ||
| extern-var-func.ll | ||
| extern-var-section.ll | ||
| extern-var-struct-weak.ll | ||
| extern-var-struct.ll | ||
| extern-var-weak-section.ll | ||
| filename.ll | ||
| float.ll | ||
| func-func-ptr.ll | ||
| func-non-void.ll | ||
| func-source.ll | ||
| func-typedef.ll | ||
| func-unused-arg.ll | ||
| func-void.ll | ||
| fwd-no-define.ll | ||
| fwd-with-define.ll | ||
| global-var-inited.ll | ||
| global-var-sec-readonly.ll | ||
| global-var-sec.ll | ||
| int.ll | ||
| local-var-readonly-1.ll | ||
| local-var-readonly-2.ll | ||
| local-var.ll | ||
| longlong.ll | ||
| map-def-2.ll | ||
| map-def-3.ll | ||
| map-def.ll | ||
| pruning-const.ll | ||
| pruning-multi-derived-type.ll | ||
| pruning-typedef.ll | ||
| ptr-const-void.ll | ||
| ptr-func-1.ll | ||
| ptr-func-2.ll | ||
| ptr-func-3.ll | ||
| ptr-int.ll | ||
| ptr-prune-type.ll | ||
| ptr-void.ll | ||
| ptr-volatile-const-void.ll | ||
| ptr-volatile-void.ll | ||
| restrict-ptr.ll | ||
| short.ll | ||
| static-func.ll | ||
| static-var-derived-type.ll | ||
| static-var-inited-sec.ll | ||
| static-var-inited.ll | ||
| static-var-readonly-sec.ll | ||
| static-var-readonly.ll | ||
| static-var-sec.ll | ||
| static-var-zerolen-array.ll | ||
| static-var.ll | ||
| struct-anon-2.ll | ||
| struct-anon.ll | ||
| struct-basic.ll | ||
| struct-bitfield-typedef.ll | ||
| struct-enum.ll | ||
| tag-1.ll | ||
| tag-2.ll | ||
| tag-typedef.ll | ||
| type-tag-fixup-fwd.ll | ||
| type-tag-fixup-resolved.ll | ||
| type-tag-var.ll | ||
| uchar.ll | ||
| uint.ll | ||
| ulonglong.ll | ||
| union-array-typedef.ll | ||
| ushort.ll | ||
| weak-global-2.ll | ||
| weak-global-3.ll | ||
| weak-global.ll | ||