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ManualDWARFIndex: Treat DW_TAG_subprogram and DW_TAG_inlined_subrouti…
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…ne the same way

Summary:
We were treating subprograms and inlined subroutines differently when
building the index. The difference was in which indexes were individual
tags inserted (subprograms went to all indexes, where as inlined
subroutines only into the basename and full name indexes).

This seems like an error, because an inlined subroutine can still
represent an C++ or an ObjC method. I don't see anything in the
subprogram branch which should not apply to an inlined subroutine, so I
propose to just treat them identically. This makes searching for an
inlined method behave the same way as for the apple index.

I write an assembly-based test because I did not want to depend on
particular clang inlining behavior (and because I wanted to see how hard
would it be).

Reviewers: clayborg, JDevlieghere

Subscribers: eraman, lldb-commits

Differential Revision: https://reviews.llvm.org/D47368

llvm-svn: 333398
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@labath
labath committed May 29, 2018
1 parent fa213f7 commit 9c3d1f4
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Showing 3 changed files with 154 additions and 23 deletions.
152 changes: 152 additions & 0 deletions lldb/lit/SymbolFile/DWARF/find-inline-method.s
View file
@@ -0,0 +1,152 @@
# REQUIRES: lld

# RUN: llvm-mc -triple x86_64-pc-linux %s -filetype=obj > %t.o
# RUN: ld.lld %t.o -o %t
# RUN: lldb-test symbols --find=function --name=inl --function-flags=method %t \
# RUN: | FileCheck %s

# CHECK: Function: {{.*}} mangled = "_Z8externali"
# CHECK: Blocks: {{.*}} range = [0x00201000-0x00201002)
# CHECK-NEXT: range = [0x00201000-0x00201002), name = "inl", mangled = _ZN1S3inlEi


# Generated via:
# clang -O2 -g -S

# from file:
# int forward(int);
# struct S {
# static int inl(int a) { return forward(a); }
# };
# int external(int a) { return S::inl(a); }

# and then simplified.

.text
_Z8externali:
.Lfunc_begin0:
jmp _Z7forwardi
.Lfunc_end0:

.globl _start
_start:
_Z7forwardi:
ret

.section .debug_str,"MS",@progbits,1
.Linfo_string0:
.asciz "clang version 7.0.0 (trunk 332830) (llvm/trunk 332835) with manual modifications"
.Linfo_string3:
.asciz "_ZN1S3inlEi"
.Linfo_string4:
.asciz "inl"
.Linfo_string6:
.asciz "S"
.Linfo_string8:
.asciz "_Z8externali"
.Linfo_string9:
.asciz "external"
.section .debug_abbrev,"",@progbits
.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 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 2 # Abbreviation Code
.byte 19 # DW_TAG_structure_type
.byte 1 # DW_CHILDREN_yes
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 11 # DW_AT_byte_size
.byte 11 # DW_FORM_data1
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 3 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 0 # DW_CHILDREN_no
.byte 110 # DW_AT_linkage_name
.byte 14 # DW_FORM_strp
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 6 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 0 # DW_CHILDREN_no
.byte 71 # DW_AT_specification
.byte 19 # DW_FORM_ref4
.byte 32 # DW_AT_inline
.byte 11 # DW_FORM_data1
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 8 # Abbreviation Code
.byte 46 # DW_TAG_subprogram
.byte 1 # DW_CHILDREN_yes
.byte 17 # DW_AT_low_pc
.byte 1 # DW_FORM_addr
.byte 18 # DW_AT_high_pc
.byte 6 # DW_FORM_data4
.byte 110 # DW_AT_linkage_name
.byte 14 # DW_FORM_strp
.byte 3 # DW_AT_name
.byte 14 # DW_FORM_strp
.byte 0 # EOM(1)
.byte 0 # EOM(2)
.byte 10 # Abbreviation Code
.byte 29 # DW_TAG_inlined_subroutine
.byte 1 # DW_CHILDREN_yes
.byte 49 # DW_AT_abstract_origin
.byte 19 # DW_FORM_ref4
.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)
.section .debug_info,"",@progbits
.Lcu_begin0:
.long .Lcu_end0-.Lcu_start0 # Length of Unit
.Lcu_start0:
.short 4 # DWARF version number
.long .debug_abbrev # Offset Into Abbrev. Section
.byte 8 # Address Size (in bytes)
.byte 1 # Abbrev [1] 0xb:0x9e DW_TAG_compile_unit
.long .Linfo_string0 # DW_AT_producer
.short 4 # DW_AT_language
.quad .Lfunc_begin0 # DW_AT_low_pc
.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
.byte 2 # Abbrev [2] 0x2a:0x1f DW_TAG_structure_type
.long .Linfo_string6 # DW_AT_name
.byte 1 # DW_AT_byte_size
.Linl_spec:
.byte 3 # Abbrev [3] 0x33:0x15 DW_TAG_subprogram
.long .Linfo_string3 # DW_AT_linkage_name
.long .Linfo_string4 # DW_AT_name
.byte 0 # End Of Children Mark
.Linl_abstract:
.byte 6 # Abbrev [6] 0x50:0x12 DW_TAG_subprogram
.long .Linl_spec # DW_AT_specification
.byte 1 # DW_AT_inline
.Linl_a_abstract:
.byte 8 # Abbrev [8] 0x62:0x46 DW_TAG_subprogram
.quad .Lfunc_begin0 # DW_AT_low_pc
.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
.long .Linfo_string8 # DW_AT_linkage_name
.long .Linfo_string9 # DW_AT_name
.byte 10 # Abbrev [10] 0x8c:0x1b DW_TAG_inlined_subroutine
.long .Linl_abstract # DW_AT_abstract_origin
.quad .Lfunc_begin0 # DW_AT_low_pc
.long .Lfunc_end0-.Lfunc_begin0 # DW_AT_high_pc
.byte 0 # End Of Children Mark
.byte 0 # End Of Children Mark
.byte 0 # End Of Children Mark
.Lcu_end0:
2 changes: 1 addition & 1 deletion lldb/lit/SymbolFile/DWARF/lit.local.cfg
View file
@@ -1 +1 @@
config.suffixes = ['.cpp']
config.suffixes = ['.cpp', '.s']
23 changes: 1 addition & 22 deletions lldb/source/Plugins/SymbolFile/DWARF/ManualDWARFIndex.cpp
View file
Expand Up @@ -256,6 +256,7 @@ void ManualDWARFIndex::IndexUnitImpl(
}

switch (tag) {
case DW_TAG_inlined_subroutine:
case DW_TAG_subprogram:
if (has_address) {
if (name) {
Expand Down Expand Up @@ -330,28 +331,6 @@ void ManualDWARFIndex::IndexUnitImpl(
}
break;

case DW_TAG_inlined_subroutine:
if (has_address) {
if (name)
set.function_basenames.Insert(ConstString(name),
DIERef(cu_offset, die.GetOffset()));
if (mangled_cstr) {
// Make sure our mangled name isn't the same string table entry as
// our name. If it starts with '_', then it is ok, else compare the
// string to make sure it isn't the same and we don't end up with
// duplicate entries
if (name && name != mangled_cstr &&
((mangled_cstr[0] == '_') ||
(::strcmp(name, mangled_cstr) != 0))) {
set.function_fullnames.Insert(ConstString(mangled_cstr),
DIERef(cu_offset, die.GetOffset()));
}
} else
set.function_fullnames.Insert(ConstString(name),
DIERef(cu_offset, die.GetOffset()));
}
break;

case DW_TAG_array_type:
case DW_TAG_base_type:
case DW_TAG_class_type:
Expand Down

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