DWARFVerifier: Enhance validation of .debug_names hash tables
Summary:
This patch adds more checks to the .debug_names validator. Specifically,
they check for:
- buckets claiming to be non-empty but pointing to mismatched hashes
(most consumers would interpret this as an empty bucket, but it
questionable whether the generator meant that)
- hashes that are not reachable from any bucket
- names with incorrect hashes
Together, these checks ensure that any name in the index can be reached
through the hash table using the regular lookup algorithm. We also warn
if we encounter a name index without a hash table.
Reviewers: JDevlieghere, aprantl, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44433
llvm-svn: 327699
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-unhashed-names.s b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-unhashed-names.s
new file mode 100644
index 0000000..cd9bbcd
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-verify-unhashed-names.s
@@ -0,0 +1,123 @@
+# RUN: llvm-mc -triple x86_64-pc-linux %s -filetype=obj | \
+# RUN: not llvm-dwarfdump -verify - | FileCheck %s
+
+# CHECK: Name Index @ 0x0: Name table entries [1, 1] are not covered by the hash table.
+# CHECK: Name Index @ 0x0: Name table entries [4, 4] are not covered by the hash table.
+ .section .debug_str,"MS",@progbits,1
+.Lstring_foo:
+ .asciz "foo"
+.Lstring_bar:
+ .asciz "bar"
+.Lstring_baz:
+ .asciz "baz"
+.Lstring_barfuz:
+ .asciz "barfuz"
+.Lstring_producer:
+ .asciz "Hand-written dwarf"
+
+ .section .debug_abbrev,"",@progbits
+.Lsection_abbrev:
+ .byte 1 # Abbreviation Code
+ .byte 17 # DW_TAG_compile_unit
+ .byte 1 # DW_CHILDREN_yes
+ .byte 37 # DW_AT_producer
+ .byte 14 # DW_FORM_strp
+ .byte 19 # DW_AT_language
+ .byte 5 # DW_FORM_data2
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 2 # Abbreviation Code
+ .byte 46 # DW_TAG_subprogram
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 63 # DW_AT_external
+ .byte 25 # DW_FORM_flag_present
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 0 # EOM(3)
+
+ .section .debug_info,"",@progbits
+.Lcu_begin0:
+ .long .Lcu_end0-.Lcu_start0 # Length of Unit
+.Lcu_start0:
+ .short 4 # DWARF version number
+ .long .Lsection_abbrev # Offset Into Abbrev. Section
+ .byte 8 # Address Size (in bytes)
+ .byte 1 # Abbrev [1] DW_TAG_compile_unit
+ .long .Lstring_producer # DW_AT_producer
+ .short 12 # DW_AT_language
+.Ldie_foo:
+ .byte 2 # Abbrev [2] DW_TAG_subprogram
+ .long .Lstring_foo # DW_AT_name
+ # DW_AT_external
+.Ldie_bar:
+ .byte 2 # Abbrev [2] DW_TAG_subprogram
+ .long .Lstring_bar # DW_AT_name
+ # DW_AT_external
+.Ldie_baz:
+ .byte 2 # Abbrev [2] DW_TAG_subprogram
+ .long .Lstring_baz # DW_AT_name
+ # DW_AT_external
+.Ldie_barfuz:
+ .byte 2 # Abbrev [2] DW_TAG_subprogram
+ .long .Lstring_barfuz # DW_AT_name
+ # DW_AT_external
+ .byte 0 # End Of Children Mark
+.Lcu_end0:
+
+ .section .debug_names,"",@progbits
+ .long .Lnames_end0-.Lnames_start0 # Header: contribution length
+.Lnames_start0:
+ .short 5 # Header: version
+ .short 0 # Header: padding
+ .long 1 # Header: compilation unit count
+ .long 0 # Header: local type unit count
+ .long 0 # Header: foreign type unit count
+ .long 2 # Header: bucket count
+ .long 4 # Header: name count
+ .long .Lnames_abbrev_end0-.Lnames_abbrev_start0 # Header: abbreviation table size
+ .long 0 # Header: augmentation length
+ .long .Lcu_begin0 # Compilation unit 0
+ .long 2 # Bucket 0
+ .long 3 # Bucket 1
+ .long 193491849 # Hash in no Bucket
+ .long 193487034 # Hash in Bucket 0
+ .long 4086570991 # Hash in Bucket 1
+ .long 193487042 # Hash in no Bucket
+ .long .Lstring_foo # String in no Bucket
+ .long .Lstring_bar # String in Bucket 0
+ .long .Lstring_barfuz # String in Bucket 1
+ .long .Lstring_baz # String in no Bucket
+ .long .Lnames0-.Lnames_entries0 # Offset in no Bucket
+ .long .Lnames1-.Lnames_entries0 # Offset in Bucket 0
+ .long .Lnames2-.Lnames_entries0 # Offset in Bucket 1
+ .long .Lnames3-.Lnames_entries0 # Offset in no Bucket
+.Lnames_abbrev_start0:
+ .byte 46 # Abbrev code
+ .byte 46 # DW_TAG_subprogram
+ .byte 3 # DW_IDX_die_offset
+ .byte 6 # DW_FORM_data4
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev
+ .byte 0 # End of abbrev list
+.Lnames_abbrev_end0:
+.Lnames_entries0:
+.Lnames0:
+ .byte 46 # Abbrev code
+ .long .Ldie_foo-.Lcu_begin0 # DW_IDX_die_offset
+ .long 0 # End of list: foo
+.Lnames1:
+ .byte 46 # Abbrev code
+ .long .Ldie_bar-.Lcu_begin0 # DW_IDX_die_offset
+ .long 0 # End of list: bar
+.Lnames2:
+ .byte 46 # Abbrev code
+ .long .Ldie_baz-.Lcu_begin0 # DW_IDX_die_offset
+ .long 0 # End of list: baz
+.Lnames3:
+ .byte 46 # Abbrev code
+ .long .Ldie_barfuz-.Lcu_begin0# DW_IDX_die_offset
+ .long 0 # End of list: barfuz
+ .p2align 2
+.Lnames_end0: