[llvm] Fix merging of debug_str_offsets with multiple contributions (PR #90461)

[Morten larsen via llvm-commits]

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@@ -0,0 +1,161 @@
+RUN: rm -rf %t && split-file %s %t && cd %t
+RUN: llc a.ll -o a.o -filetype=obj --split-dwarf-output=a.dwo --split-dwarf-file=a.dwo
+RUN: llc b.ll -o b.o -filetype=obj --split-dwarf-output=b.dwo --split-dwarf-file=b.dwo
+RUN: llc c.ll -o c.o -filetype=obj --split-dwarf-output=c.dwo --split-dwarf-file=c.dwo
+RUN: llvm-dwp a.dwo b.dwo -o ab.dwp
+RUN: llvm-dwp c.dwo ab.dwp -o merged.dwp
+RUN: llvm-dwarfdump -v merged.dwp | FileCheck --check-prefix=CHECK %s
+
+CHECK-LABEL: .debug_abbrev.dwo contents:
+CHECK-LABEL: Abbrev table for offset:
+CHECK: 0x0000[[CAOFF:.*]]
+CHECK-LABEL: Abbrev table for offset:
+CHECK: 0x0000[[AAOFF:.*]]
+CHECK-LABEL: Abbrev table for offset:
+CHECK: 0x0000[[BAOFF:.*]]
+
+CHECK: .debug_info.dwo contents:
+CHECK: 0x[[#%.8x,COFF:]]:
+CHECK-LABEL: Compile Unit: length = {{.*}}, format = DWARF32, version = 0x0005, unit_type = DW_UT_split_compile, abbr_offset =
+CHECK:         0x[[CAOFF]], addr_size = 0x08, DWO_id = 0x[[DWOC:.*]] (next unit at 0x[[#%.8x,BOFF:]])
+CHECK: [[#BOFF]]:
+CHECK-LABEL: Compile Unit: length = {{.*}}, format = DWARF32, version = 0x0005, unit_type = DW_UT_split_compile, abbr_offset =
+CHECK:         0x[[BAOFF]], addr_size = 0x08, DWO_id = 0x[[DWOB:.*]] (next unit at 0x[[#%.8x,AOFF:]])
+CHECK: [[#AOFF]]:
+CHECK-LABEL: Compile Unit: length = {{.*}}, format = DWARF32, version = 0x0005, unit_type = DW_UT_split_compile, abbr_offset =
+CHECK:         0x[[AAOFF]], addr_size = 0x08, DWO_id = 0x[[DWOA:.*]] (next unit at 0x[[#%.8x,XOFF:]])
+
+CHECK-LABEL: .debug_cu_index contents:
+CHECK:    Index Signature          INFO                                     ABBREV                                  STR_OFFSETS 
+CHECK-DAG:       [[DWOC]]  [0x00000000[[#COFF]], 0x00000000[[#BOFF]]) [0x0000[[CAOFF]], 0x0000[[AAOFF]]) [0x00000000, 0x00000024) 
+CHECK-DAG:       [[DWOB]]  [0x00000000[[#BOFF]], 0x00000000[[#AOFF]]) [0x0000[[BAOFF]],  
+CHECK-DAG:       [[DWOA]]  [0x00000000[[#AOFF]], 0x00000000[[#XOFF]]) [0x0000[[AAOFF]], 
+
+CHECK-LABEL: .debug_str_offsets.dwo contents:
+CHECK: Contribution size = 32, Format = DWARF32, Version = 5
+CHECK: Contribution size = 24, Format = DWARF32, Version = 5
+CHECK: Contribution size = 28, Format = DWARF32, Version = 5
+
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molar wrote:

I have added a verbose check of the contents, let me know if there is a better way to do it, other than just comparing against the output. 

https://github.com/llvm/llvm-project/pull/90461