[PATCH] D58357: [LLD] add test for line number info related to differrent .text sections
George Rimar via Phabricator via llvm-commits
llvm-commits at lists.llvm.org
Tue Feb 19 03:33:47 PST 2019
grimar added a comment.
It is not clear from the description, so for other reviewers:
This test now passes without any LLD code changes.
This is relative to D58194 <https://reviews.llvm.org/D58194>, which changes the DWARF parsers interface slightly and
also makes a change on LLD side to conform to that interface.
LLD currently contains kind of hack (we have a TODO saying we want to remove it):
we update the relocation values by a `getOffsetInFile` for the purpose of error reporting:
https://github.com/llvm-mirror/lld/blob/master/ELF/DWARF.cpp#L88
https://github.com/llvm-mirror/lld/blob/master/ELF/InputFiles.cpp#L213
D58194 <https://reviews.llvm.org/D58194> perhaps might allow us to revisit these places and remove the "TODO",
but I think it is nice to have a test case in LLD for the situation fixed in D58194 <https://reviews.llvm.org/D58194> in any case.
================
Comment at: lld/test/ELF/debug-line-obj.s:9
+# flag and addresses are not assigned to sections yet. In that case
+# .debug_line contains overlapping addresses.
+
----------------
I am not sure it is clear enough to say that .debug_line contains overlapping addresses, it contains
unrelocated addresses, which are technically offsets and "overlaps" only because were not yet relocated.
I would suggest the following rewording:
> When compiling with -ffunction-sections, .debug_line may contain descriptions of locations from the different text sections. Until relocated such descriptions might contain overlapping offsets. Check LLD is able to report the error locations correctly in this case.
================
Comment at: lld/test/ELF/debug-line-obj.s:252
+ .section .debug_line,"", at progbits
+.Lline_table_start0:
----------------
It's a good practice to reduce the sample if possible.
It is hard to do for DWARF asm usually, but some of the parts
were obviously unused in the test, so I removed them, please use:
```
.text
.file "test.cpp"
.section .text._Z3barv,"ax", at progbits
.globl _Z3barv
.type _Z3barv, at function
_Z3barv:
.Lfunc_begin0:
.file 0 "/path" "test.cpp" md5 0x9ff11a8404ab4d032ee2dd4f5f8c4140
.file 1 "test.cpp" md5 0x9ff11a8404ab4d032ee2dd4f5f8c4140
.loc 1 2 0 # test.cpp:2:0
.loc 1 2 20 prologue_end # test.cpp:2:20
callq _Z3foov
.loc 1 2 13 is_stmt 0 # test.cpp:2:13
.Lfunc_end0:
.size _Z3barv, .Lfunc_end0-_Z3barv
# -- End function
.section .text._Z3bazv,"ax", at progbits
.globl _Z3bazv # -- Begin function _Z3bazv
.type _Z3bazv, at function
_Z3bazv: # @_Z3bazv
.Lfunc_begin1:
.loc 1 3 0 is_stmt 1 # test.cpp:3:0
.loc 1 3 20 prologue_end # test.cpp:3:20
callq _Z3foov
.loc 1 3 13 is_stmt 0 # test.cpp:3:13
.Lfunc_end1:
.size _Z3bazv, .Lfunc_end1-_Z3bazv
.section .debug_str,"MS", at progbits,1
.Linfo_string0:
.asciz "stub"
.section .debug_str_offsets,"", at progbits
.long 8
.short 5
.short 0
.Lstr_offsets_base0:
.long .Linfo_string0
.section .debug_abbrev,"", at progbits
.byte 1 # Abbreviation Code
.byte 17 # DW_TAG_compile_unit
.byte 1 # DW_CHILDREN_yes
.byte 37 # DW_AT_producer
.byte 37 # DW_FORM_strx1
.byte 19 # DW_AT_language
.byte 5 # DW_FORM_data2
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.byte 114 # DW_AT_str_offsets_base
.byte 23 # DW_FORM_sec_offset
.byte 16 # DW_AT_stmt_list
.byte 23 # DW_FORM_sec_offset
.byte 27 # DW_AT_comp_dir
.byte 37 # DW_FORM_strx1
.byte 115 # DW_AT_addr_base
.byte 23 # DW_FORM_sec_offset
.byte 17 # DW_AT_low_pc
.byte 1 # DW_FORM_addr
.byte 85 # DW_AT_ranges
.byte 35 # DW_FORM_rnglistx
.byte 116 # DW_AT_rnglists_base
.byte 23 # DW_FORM_sec_offset
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 2 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 0 # DW_CHILDREN_no
.byte 17 # DW_AT_low_pc
.byte 27 # DW_FORM_addrx
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 64 # DW_AT_frame_base
.byte 24 # DW_FORM_exprloc
.byte 110 # DW_AT_linkage_name
.byte 37 # DW_FORM_strx1
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.byte 58 # DW_AT_decl_file
.byte 11 # DW_FORM_data1
.byte 59 # DW_AT_decl_line
.byte 11 # DW_FORM_data1
.byte 73 # DW_AT_type
.byte 19 # DW_FORM_ref4
.byte 63 # DW_AT_external
.byte 25 # DW_FORM_flag_present
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 3 # Abbreviation Code
.byte 36 # DW_TAG_base_type
.byte 0 # DW_CHILDREN_no
.byte 3 # DW_AT_name
.byte 37 # DW_FORM_strx1
.byte 62 # DW_AT_encoding
.byte 11 # DW_FORM_data1
.byte 11 # DW_AT_byte_size
.byte 11 # DW_FORM_data1
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 0 # EOM(3)
.section .debug_info,"", at progbits
.Lcu_begin0:
.long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
.Ldebug_info_start0:
.short 5 # DWARF version number
.byte 1 # DWARF Unit Type
.byte 8 # Address Size (in bytes)
.long .debug_abbrev # Offset Into Abbrev. Section
.byte 1 # Abbrev [1] 0xc:0x44 DW_TAG_compile_unit
.byte 0 # DW_AT_producer
.short 4 # DW_AT_language
.byte 0 # DW_AT_name
.long .Lstr_offsets_base0 # DW_AT_str_offsets_base
.long .Lline_table_start0 # DW_AT_stmt_list
.byte 2 # DW_AT_comp_dir
.long 0 # DW_AT_addr_base
.quad 0 # DW_AT_low_pc
.byte 0 # DW_AT_ranges
.long 0 # DW_AT_rnglists_base
.byte 2 # Abbrev [2] 0x2b:0x10 DW_TAG_subprogram
.byte 0 # DW_AT_low_pc
.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
.byte 1 # DW_AT_frame_base
.byte 86
.byte 3 # DW_AT_linkage_name
.byte 0 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 2 # DW_AT_decl_line
.long 75 # DW_AT_type
# DW_AT_external
.byte 2 # Abbrev [2] 0x3b:0x10 DW_TAG_subprogram
.byte 1 # DW_AT_low_pc
.long .Lfunc_end1-.Lfunc_begin1 # DW_AT_high_pc
.byte 1 # DW_AT_frame_base
.byte 86
.byte 6 # DW_AT_linkage_name
.byte 0 # DW_AT_name
.byte 1 # DW_AT_decl_file
.byte 3 # DW_AT_decl_line
.long 75 # DW_AT_type
# DW_AT_external
.byte 3 # Abbrev [3] 0x4b:0x4 DW_TAG_base_type
.byte 0 # DW_AT_name
.byte 5 # DW_AT_encoding
.byte 4 # DW_AT_byte_size
.byte 0 # End Of Children Mark
.Ldebug_info_end0:
.section .debug_line,"", at progbits
.Lline_table_start0:
```
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D58357/new/
https://reviews.llvm.org/D58357
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