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Differential D85579 Diff 284114 lld/test/ELF/gdb-index-dwarf5-type-unit.s

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lld/test/ELF/gdb-index-dwarf5-type-unit.s

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				# REQUIRES: x86
				## -gdwarf-5 -fdebug-types-section may produce multiple .debug_info sections.
				## All except one are type units. Test we can locate the compile unit, add it to
				## the index, and not erroneously duplicate it (which would happen if we
				## consider every .debug_info a compile unit).

				# RUN: llvm-mc -filetype=obj -triple=x86_64 %s -o %t.o
				# RUN: ld.lld --gdb-index -Ttext=0x1000 %t.o -o %t
				# RUN: llvm-dwarfdump --gdb-index %t \| FileCheck %s

				## Test we don't uncompress a section while another thread is concurrently
				## accessing it. This would be detected by tsan as a data race.
				# RUN: llvm-objcopy --compress-debug-sections %t.o
				# RUN: ld.lld --gdb-index -Ttext=0x1000 %t.o -o %t1
				# RUN: llvm-dwarfdump --gdb-index %t1 \| FileCheck %s

				## In this test, there are actually two compile unit .debug_info (very uncommon;
				## -r --unique). Currently we only handle the last compile unit.
				# CHECK: CU list offset = 0x18, has 1 entries:
				# CHECK-NEXT: 0: Offset = 0x32, Length = 0x19

				# CHECK: Address area offset = 0x28, has 1 entries:
				# CHECK-NEXT: Low/High address = [0x1001, 0x1002) (Size: 0x1), CU id = 0

				.Lfunc_begin0:
				ret
				.Lfunc_end0:
				.Lfunc_begin1:
				ret
				.Lfunc_end1:

				.section .debug_abbrev,"",@progbits
				.byte 1 # Abbreviation Code
				.byte 65 # DW_TAG_type_unit
				.byte 0 # DW_CHILDREN_no
				.byte 0 # EOM(1)
				.byte 0 # EOM(2)

				.byte 2 # Abbreviation Code
				.byte 17 # DW_TAG_compile_unit
				.byte 0 # DW_CHILDREN_no
				.byte 17 # DW_AT_low_pc
				.byte 1 # DW_FORM_addr
				.byte 18 # DW_AT_high_pc
				.byte 6 # DW_FORM_data4
				.byte 0 # EOM(1)
				.byte 0 # EOM(2)

				.byte 0 # EOM(3)

				.macro TYPE_UNIT id signature
				.section .debug_info,"G",@progbits,\signature
				MaskRayAuthorUnsubmitted Done Reply Inline Actions @dblaikie Does this test achieve a good minimality/robustness/usefulness in your opinion? MaskRay: @dblaikie Does this test achieve a good minimality/robustness/usefulness in your opinion?
				dblaikieUnsubmitted Not Done Reply Inline Actions I think so? If I'm reading it correctly it's a type unit in a comdat, a compile unit, another compile unit in a distinct fragment of debug_info, and then another type unit in a comdat? The existence of two compilation units in separate sections with the same name isn't a use case I know of any producer producing today - but if it helps test out the generality of this functionality, it sounds OK to me. dblaikie: I think so? If I'm reading it correctly it's a type unit in a comdat, a compile unit, another…
				MaskRayAuthorUnsubmitted Done Reply Inline Actions Thanks for confirmation. The existence of two compilation units in separate sections with the same name isn't a use case I know of any producer producing today - but if it helps test out the generality of this functionality, it sounds OK to me. This is super rare. `ld -r --unique` can create the case. I just want to make the behavior clearer/concise without adding another test. MaskRay: Thanks for confirmation. > The existence of two compilation units in separate sections with…
				dblaikieUnsubmitted Not Done Reply Inline Actions Ah, sounds good! dblaikie: Ah, sounds good!
				.long .Ldebug_info_end\id-.Ldebug_info_start\id # Length of Unit
				.Ldebug_info_start\id:
				.short 5 # DWARF version number
				.byte 2 # DWARF Unit Type
				.byte 8 # Address Size
				.long .debug_abbrev # Offset Into Abbrev. Section
				.quad \signature # Type Signature
				.long .Ldebug_info_end\id # Type DIE Offset
				.byte 1 # Abbrev [1] DW_TAG_type_unit
				.Ldebug_info_end\id:
				.endm

				## We place compile units between two type units (rare). A naive approach will
				## take either the first or the last .debug_info
				TYPE_UNIT 0, 123

				.section .debug_info,"",@progbits,unique,0
				.Lcu_begin0:
				.long .Lcu_end0-.Lcu_begin0-4 # Length of Unit
				.short 5 # DWARF version number
				.byte 1 # DWARF Unit Type
				.byte 8 # Address Size
				.long .debug_abbrev # Offset Into Abbrev. Section
				.byte 2 # Abbrev [2] DW_TAG_compile_unit
				.quad .Lfunc_begin0 # DW_AT_low_pc
				.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
				.Lcu_end0:

				.section .debug_info,"",@progbits,unique,1
				.Lcu_begin1:
				.long .Lcu_end1-.Lcu_begin1-4 # Length of Unit
				.short 5 # DWARF version number
				.byte 1 # DWARF Unit Type
				.byte 8 # Address Size
				.long .debug_abbrev # Offset Into Abbrev. Section
				.byte 2 # Abbrev [2] DW_TAG_compile_unit
				.quad .Lfunc_begin1 # DW_AT_low_pc
				.long .Lfunc_end1-.Lfunc_begin1 # DW_AT_high_pc
				.Lcu_end1:

				TYPE_UNIT 1, 456