dwarfgen: Add support for generating the debug_str_offsets section, take 2
This recommits r337910 after fixing an "ambiguous call to addAttribute"
error with some compilers (gcc circa 4.9 and MSVC). It seems that these
compilers will consider a "false -> pointer" conversion during overload
resolution. This creates ambiguity because one I added an overload which
takes a MCExpr * as an argument.
I fix this by making the new overload take MCExpr&, which avoids the
conversion. It also documents the fact that we expect a valid MCExpr
object.
Original commit message follows:
The motivation for this is D49493, where we'd like to test details of
debug_str_offsets behavior which is difficult to trigger from a
traditional test.
This adds the plubming necessary for dwarfgen to generate this section.
The more interesting changes are:
- I've moved emitStringOffsetsTableHeader function from DwarfFile to
DwarfStringPool, so I can generate the section header more easily from
the unit test.
- added a new addAttribute overload taking an MCExpr*. This is used to
generate the DW_AT_str_offsets_base, which links a compile unit to the
offset table.
I've also added a basic test for reading and writing DW_form_strx forms.
Reviewers: dblaikie, JDevlieghere, probinson
Subscribers: llvm-commits, aprantl
Differential Revision: https://reviews.llvm.org/D49670
llvm-svn: 337933
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
index 6b26318..60058be 100644
--- a/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp
@@ -67,12 +67,23 @@
const uint32_t Dwarf32Values[] = {1, 2, 3, 4, 5, 6, 7, 8};
const char *StringValue = "Hello";
const char *StrpValue = "World";
+ const char *StrxValue = "Indexed";
+ const char *Strx1Value = "Indexed1";
+ const char *Strx2Value = "Indexed2";
+ const char *Strx3Value = "Indexed3";
+ const char *Strx4Value = "Indexed4";
auto ExpectedDG = dwarfgen::Generator::create(Triple, Version);
ASSERT_THAT_EXPECTED(ExpectedDG, Succeeded());
dwarfgen::Generator *DG = ExpectedDG.get().get();
dwarfgen::CompileUnit &CU = DG->addCompileUnit();
dwarfgen::DIE CUDie = CU.getUnitDIE();
+
+ if (Version >= 5)
+ CUDie.addAttribute(dwarf::DW_AT_str_offsets_base, dwarf::DW_FORM_sec_offset,
+ *MCSymbolRefExpr::create(DG->getStringOffsetsStartSym(),
+ *DG->getMCContext()));
+
uint16_t Attr = DW_AT_lo_user;
//----------------------------------------------------------------------
@@ -122,6 +133,19 @@
const auto Attr_DW_FORM_string = static_cast<dwarf::Attribute>(Attr++);
CUDie.addAttribute(Attr_DW_FORM_string, DW_FORM_string, StringValue);
+ const auto Attr_DW_FORM_strx = static_cast<dwarf::Attribute>(Attr++);
+ const auto Attr_DW_FORM_strx1 = static_cast<dwarf::Attribute>(Attr++);
+ const auto Attr_DW_FORM_strx2 = static_cast<dwarf::Attribute>(Attr++);
+ const auto Attr_DW_FORM_strx3 = static_cast<dwarf::Attribute>(Attr++);
+ const auto Attr_DW_FORM_strx4 = static_cast<dwarf::Attribute>(Attr++);
+ if (Version >= 5) {
+ CUDie.addAttribute(Attr_DW_FORM_strx, DW_FORM_strx, StrxValue);
+ CUDie.addAttribute(Attr_DW_FORM_strx1, DW_FORM_strx1, Strx1Value);
+ CUDie.addAttribute(Attr_DW_FORM_strx2, DW_FORM_strx2, Strx2Value);
+ CUDie.addAttribute(Attr_DW_FORM_strx3, DW_FORM_strx3, Strx3Value);
+ CUDie.addAttribute(Attr_DW_FORM_strx4, DW_FORM_strx4, Strx4Value);
+ }
+
const auto Attr_DW_FORM_strp = static_cast<dwarf::Attribute>(Attr++);
CUDie.addAttribute(Attr_DW_FORM_strp, DW_FORM_strp, StrpValue);
@@ -281,11 +305,33 @@
//----------------------------------------------------------------------
auto ExtractedStringValue = toString(DieDG.find(Attr_DW_FORM_string));
EXPECT_TRUE((bool)ExtractedStringValue);
- EXPECT_TRUE(strcmp(StringValue, *ExtractedStringValue) == 0);
+ EXPECT_STREQ(StringValue, *ExtractedStringValue);
+
+ if (Version >= 5) {
+ auto ExtractedStrxValue = toString(DieDG.find(Attr_DW_FORM_strx));
+ EXPECT_TRUE((bool)ExtractedStrxValue);
+ EXPECT_STREQ(StrxValue, *ExtractedStrxValue);
+
+ auto ExtractedStrx1Value = toString(DieDG.find(Attr_DW_FORM_strx1));
+ EXPECT_TRUE((bool)ExtractedStrx1Value);
+ EXPECT_STREQ(Strx1Value, *ExtractedStrx1Value);
+
+ auto ExtractedStrx2Value = toString(DieDG.find(Attr_DW_FORM_strx2));
+ EXPECT_TRUE((bool)ExtractedStrx2Value);
+ EXPECT_STREQ(Strx2Value, *ExtractedStrx2Value);
+
+ auto ExtractedStrx3Value = toString(DieDG.find(Attr_DW_FORM_strx3));
+ EXPECT_TRUE((bool)ExtractedStrx3Value);
+ EXPECT_STREQ(Strx3Value, *ExtractedStrx3Value);
+
+ auto ExtractedStrx4Value = toString(DieDG.find(Attr_DW_FORM_strx4));
+ EXPECT_TRUE((bool)ExtractedStrx4Value);
+ EXPECT_STREQ(Strx4Value, *ExtractedStrx4Value);
+ }
auto ExtractedStrpValue = toString(DieDG.find(Attr_DW_FORM_strp));
EXPECT_TRUE((bool)ExtractedStrpValue);
- EXPECT_TRUE(strcmp(StrpValue, *ExtractedStrpValue) == 0);
+ EXPECT_STREQ(StrpValue, *ExtractedStrpValue);
//----------------------------------------------------------------------
// Test reference forms