Implement equal_range for the DWARF v5 accelerator table

Summary:
This patch implements the name lookup functionality of the .debug_names
accelerator table and hooks it up to "llvm-dwarfdump -find". To make the
interface of the two kinds of accelerator tables more consistent, I've
created an abstract "DWARFAcceleratorTable::Entry" class, which provides
a consistent interface to access the common functionality of the table
entries (such as getting the die offset, die tag, etc.). I've also
modified the apple table to vend entries conforming to this interface.

Reviewers: JDevlieghere, aprantl, probinson, dblaikie

Subscribers: vleschuk, clayborg, echristo, llvm-commits

Differential Revision: https://reviews.llvm.org/D43067

llvm-svn: 326003

1 files changed, 182 insertions, 0 deletions

diff --git a/llvm/test/tools/llvm-dwarfdump/X86/debug-names-find.s b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-find.s
new file mode 100644
index 00000000000..280c3d771b0
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/X86/debug-names-find.s
@@ -0,0 +1,182 @@
+# RUN: llvm-mc -triple x86_64-pc-linux %s -filetype=obj -o %t
+# RUN: llvm-dwarfdump -find=foo %t | FileCheck --check-prefix=FOO %s
+# RUN: llvm-dwarfdump -find=baz %t | FileCheck --check-prefix=BAZ %s
+# RUN: llvm-dwarfdump -find=missing %t | FileCheck --check-prefix=MISSING %s
+
+# FOO: DW_TAG_subprogram
+# FOO-NEXT: DW_AT_name ("foo")
+# FOO-NEXT: DW_AT_external
+
+# BAZ: DW_TAG_subprogram
+# BAZ-NEXT: DW_AT_name ("baz")
+# BAZ-NEXT: DW_AT_external
+
+# MISSING-NOT: foo
+# MISSING-NOT: bar
+# MISSING-NOT: baz
+# MISSING-NOT: bazz
+
+	.section	.debug_str,"MS",@progbits,1
+.Lstring_foo:
+	.asciz	"foo"
+.Lstring_foo_mangled:
+	.asciz	"_Z3foov"
+.Lstring_bar:
+	.asciz	"bar"
+.Lstring_baz:
+	.asciz	"baz"
+.Lstring_bazz:
+	.asciz	"bazz"
+.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
+	.byte	0                       # End Of Children Mark
+.Lcu_end0:
+
+.Lcu_begin1:
+	.long	.Lcu_end1-.Lcu_start1   # Length of Unit
+.Lcu_start1:
+	.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_baz:
+	.byte	2                       # Abbrev [2] DW_TAG_subprogram
+	.long	.Lstring_baz            # DW_AT_name
+                                        # DW_AT_external
+.Ldie_bazz:
+	.byte	2                       # Abbrev [2] DW_TAG_subprogram
+	.long	.Lstring_bazz           # DW_AT_name
+                                        # DW_AT_external
+	.byte	0                       # End Of Children Mark
+.Lcu_end1:
+
+	.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	3                       # 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	1                       # Bucket 0
+	.long	2                       # Bucket 1
+        .long   193487034               # Hash in Bucket 0
+	.long	193491849               # Hash in Bucket 1
+	.long	-1257882357             # Hash in Bucket 1
+	.long	.Lstring_bar            # String in Bucket 1: bar
+	.long	.Lstring_foo            # String in Bucket 1: foo
+	.long	.Lstring_foo_mangled    # String in Bucket 1: _Z3foov
+	.long	.Lnames0-.Lnames_entries0 # Offset in Bucket 1
+	.long	.Lnames1-.Lnames_entries0 # Offset in Bucket 1
+	.long	.Lnames2-.Lnames_entries0 # Offset in Bucket 1
+.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_bar               # DW_IDX_die_offset
+	.long	0                       # End of list: bar
+.Lnames1:
+	.byte	46                      # Abbrev code
+	.long	.Ldie_foo               # DW_IDX_die_offset
+	.long	0                       # End of list: foo
+.Lnames2:
+	.byte	46                      # Abbrev code
+	.long	.Ldie_foo               # DW_IDX_die_offset
+	.long	0                       # End of list: _Z3foov
+	.p2align	2
+.Lnames_end0:
+
+# Index of compilation unit 1. This one has no hash table.
+	.long	.Lnames_end1-.Lnames_start1 # Header: contribution length
+.Lnames_start1:
+	.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	0                       # Header: bucket count
+	.long	2                       # Header: name count
+	.long	.Lnames_abbrev_end1-.Lnames_abbrev_start1 # Header: abbreviation table size
+	.long	0                       # Header: augmentation length
+	.long	.Lcu_begin1             # Compilation unit 0
+	.long	.Lstring_baz            # String in Bucket 1: baz
+	.long	.Lstring_bazz           # String in Bucket 1: bazz
+	.long	.Lnames3-.Lnames_entries1 # Offset in Bucket 1
+	.long	.Lnames4-.Lnames_entries1 # Offset in Bucket 1
+.Lnames_abbrev_start1:
+	.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_end1:
+.Lnames_entries1:
+.Lnames3:
+	.byte	46                      # Abbrev code
+	.long	.Ldie_baz               # DW_IDX_die_offset
+	.long	0                       # End of list: baz
+	.p2align	2
+.Lnames4:
+	.byte	46                      # Abbrev code
+	.long	.Ldie_bazz              # DW_IDX_die_offset
+	.long	0                       # End of list: baz
+	.p2align	2
+.Lnames_end1: