[llvm] 77973f8 - [WebAssembly] Add support for DWARF type units
Derek Schuff via llvm-commits
llvm-commits at lists.llvm.org
Wed Oct 28 17:42:14 PDT 2020
Author: Derek Schuff
Date: 2020-10-28T17:41:22-07:00
New Revision: 77973f8dee6d4d6f1b7c2a026249c1f7068f267b
URL: https://github.com/llvm/llvm-project/commit/77973f8dee6d4d6f1b7c2a026249c1f7068f267b
DIFF: https://github.com/llvm/llvm-project/commit/77973f8dee6d4d6f1b7c2a026249c1f7068f267b.diff
LOG: [WebAssembly] Add support for DWARF type units
Since Wasm comdat sections work similarly to ELF, we can use that mechanism
to eliminate duplicate dwarf type information in the same way.
Differential Revision: https://reviews.llvm.org/D88603
Added:
llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll
Modified:
clang/lib/Driver/ToolChains/Clang.cpp
clang/test/Driver/debug-options.c
llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
llvm/lib/MC/MCObjectFileInfo.cpp
llvm/lib/MC/WasmObjectWriter.cpp
Removed:
################################################################################
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index dde4e8de531c..a15067b081b7 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -3989,7 +3989,7 @@ static void RenderDebugOptions(const ToolChain &TC, const Driver &D,
if (Args.hasFlag(options::OPT_fdebug_types_section,
options::OPT_fno_debug_types_section, false)) {
- if (!T.isOSBinFormatELF()) {
+ if (!(T.isOSBinFormatELF() || T.isOSBinFormatWasm())) {
D.Diag(diag::err_drv_unsupported_opt_for_target)
<< Args.getLastArg(options::OPT_fdebug_types_section)
->getAsString(Args)
diff --git a/clang/test/Driver/debug-options.c b/clang/test/Driver/debug-options.c
index 1be976d9743a..bedc9d044a2c 100644
--- a/clang/test/Driver/debug-options.c
+++ b/clang/test/Driver/debug-options.c
@@ -214,6 +214,9 @@
// RUN: %clang -### -fdebug-types-section -fno-debug-types-section -target x86_64-unknown-linux %s 2>&1 \
// RUN: | FileCheck -check-prefix=NOFDTS %s
//
+// RUN: %clang -### -fdebug-types-section -target wasm32-unknown-unknown %s 2>&1 \
+// RUN: | FileCheck -check-prefix=FDTS %s
+//
// RUN: %clang -### -fdebug-types-section -target x86_64-apple-darwin %s 2>&1 \
// RUN: | FileCheck -check-prefix=FDTSE %s
//
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index e460402e7941..859956e6c3a5 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -394,8 +394,9 @@ DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
UseSectionsAsReferences = DwarfSectionsAsReferences == Enable;
// Don't generate type units for unsupported object file formats.
- GenerateTypeUnits =
- A->TM.getTargetTriple().isOSBinFormatELF() && GenerateDwarfTypeUnits;
+ GenerateTypeUnits = (A->TM.getTargetTriple().isOSBinFormatELF() ||
+ A->TM.getTargetTriple().isOSBinFormatWasm()) &&
+ GenerateDwarfTypeUnits;
TheAccelTableKind = computeAccelTableKind(
DwarfVersion, GenerateTypeUnits, DebuggerTuning, A->TM.getTargetTriple());
diff --git a/llvm/lib/MC/MCObjectFileInfo.cpp b/llvm/lib/MC/MCObjectFileInfo.cpp
index d8ea0a879f2b..1349494c5436 100644
--- a/llvm/lib/MC/MCObjectFileInfo.cpp
+++ b/llvm/lib/MC/MCObjectFileInfo.cpp
@@ -963,9 +963,14 @@ MCSection *MCObjectFileInfo::getDwarfComdatSection(const char *Name,
case Triple::ELF:
return Ctx->getELFSection(Name, ELF::SHT_PROGBITS, ELF::SHF_GROUP, 0,
utostr(Hash));
+ case Triple::Wasm:
+ // FIXME: When using dwarf 5, the .debug_info section is used for type units
+ // but that section already exists, so attempting to get it as a comdate
+ // section triggers an assert.
+ return Ctx->getWasmSection(Name, SectionKind::getMetadata(), utostr(Hash),
+ MCContext::GenericSectionID);
case Triple::MachO:
case Triple::COFF:
- case Triple::Wasm:
case Triple::GOFF:
case Triple::XCOFF:
case Triple::UnknownObjectFormat:
diff --git a/llvm/lib/MC/WasmObjectWriter.cpp b/llvm/lib/MC/WasmObjectWriter.cpp
index f81a83d1651c..2f1277eb8110 100644
--- a/llvm/lib/MC/WasmObjectWriter.cpp
+++ b/llvm/lib/MC/WasmObjectWriter.cpp
@@ -1378,9 +1378,6 @@ uint64_t WasmObjectWriter::writeOneObject(MCAssembler &Asm,
MCSymbol *Begin = Sec.getBeginSymbol();
if (Begin) {
WasmIndices[cast<MCSymbolWasm>(Begin)] = CustomSections.size();
- if (SectionName != Begin->getName())
- report_fatal_error("section name and begin symbol should match: " +
- Twine(SectionName));
}
// Separate out the producers and target features sections
diff --git a/llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll b/llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll
new file mode 100644
index 000000000000..fa244d99735d
--- /dev/null
+++ b/llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll
@@ -0,0 +1,117 @@
+; RUN: llc -dwarf-version=4 -generate-type-units \
+; RUN: -filetype=obj -O0 -mtriple=wasm32-unknown-unknown < %s \
+; RUN: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=SINGLE-4
+
+; RUN: llc -split-dwarf-file=foo.dwo -split-dwarf-output=%t.dwo \
+; RUN: -dwarf-version=4 -generate-type-units \
+; RUN: -filetype=obj -O0 -mtriple=wasm32-unknown-unknown < %s \
+; RUN: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=O-4
+; RUN: llvm-dwarfdump -v %t.dwo | FileCheck %s --check-prefix=DWO-4
+
+; TODO: enable testing for dwarf v5 with type units
+; (See the FIXME in MCObjectFileInfo::getDwarfComdatSection)
+; RU N: llc -dwarf-version=5 -generate-type-units \
+; RU N: -filetype=obj -O0 -mtriple= < %s \
+; RU N: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=SINGLE-5
+
+; RU N: llc -split-dwarf-file=foo.dwo -split-dwarf-output=%t.dwo \
+; RU N: -dwarf-version=5 -generate-type-units \
+; RU N: -filetype=obj -O0 -mtriple= < %s \
+; RU N: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=O-5
+; RU N: llvm-dwarfdump -v %t.dwo | FileCheck %s --check-prefix=DWO-5
+
+; This test is derived from test/CodeGen/X86/dwarf-headers.ll
+
+; Looking for DWARF headers to be generated correctly.
+; There are 8 variants with 5 formats: v4 CU, v4 TU, v5 normal/partial CU,
+; v5 skeleton/split CU, v5 normal/split TU. Some v5 variants
diff er only
+; in the unit_type code, and the skeleton/split CU
diff ers from normal/partial
+; by having one extra field (dwo_id).
+; (v2 thru v4 CUs are all the same, and TUs were invented in v4,
+; so we don't bother checking older versions.)
+
+; Test case built from:
+;struct S {
+; int s1;
+;};
+;
+;S s;
+
+; Verify the v4 non-split headers.
+; Note that we check the exact offset of the DIEs because that tells us
+; the length of the header.
+;
+; SINGLE-4: .debug_info contents:
+; SINGLE-4: 0x00000000: Compile Unit: {{.*}} version = 0x0004, abbr_offset
+; SINGLE-4: 0x0000000b: DW_TAG_compile_unit
+;
+; SINGLE-4: .debug_types contents:
+; SINGLE-4: 0x00000000: Type Unit: {{.*}} version = 0x0004, abbr_offset
+; SINGLE-4: 0x00000017: DW_TAG_type_unit
+
+; Verify the v4 split headers.
+;
+; O-4: .debug_info contents:
+; O-4: 0x00000000: Compile Unit: {{.*}} version = 0x0004, abbr_offset
+; O-4: 0x0000000b: DW_TAG_compile_unit
+;
+; DWO-4: .debug_info.dwo contents:
+; DWO-4: 0x00000000: Compile Unit: {{.*}} version = 0x0004, abbr_offset
+; DWO-4: 0x0000000b: DW_TAG_compile_unit
+;
+; DWO-4: .debug_types.dwo contents:
+; DWO-4: 0x00000000: Type Unit: {{.*}} version = 0x0004, abbr_offset
+; DWO-4: 0x00000017: DW_TAG_type_unit
+
+; Verify the v5 non-split headers. Type units come first.
+; All .debug_info sections are reported in one go, but the offset resets for
+; each new section.
+;
+; SINGLE-5: .debug_info contents:
+; SINGLE-5: 0x00000000: Type Unit: {{.*}} version = 0x0005, unit_type = DW_UT_type, abbr_offset
+; SINGLE-5: 0x00000018: DW_TAG_type_unit
+; SINGLE-5-NOT: contents:
+; SINGLE-5: 0x00000000: Compile Unit: {{.*}} version = 0x0005, unit_type = DW_UT_compile, abbr_offset
+; SINGLE-5: 0x0000000c: DW_TAG_compile_unit
+
+; Verify the v5 split headers.
+;
+; O-5: .debug_info contents:
+; O-5: 0x00000000: Compile Unit: {{.*}} version = 0x0005, unit_type = DW_UT_skeleton, abbr_offset
+; O-5-SAME: DWO_id = 0xccd7e58ef8bf4aa6
+; O-5: 0x00000014: DW_TAG_skeleton_unit
+;
+; DWO-5: .debug_info.dwo contents:
+; DWO-5: 0x00000000: Type Unit: {{.*}} version = 0x0005, unit_type = DW_UT_split_type, abbr_offset
+; DWO-5: 0x00000018: DW_TAG_type_unit
+; DWO-5: 0x00000033: Compile Unit: {{.*}} version = 0x0005, unit_type = DW_UT_split_compile, abbr_offset
+; DWO-5-SAME: DWO_id = 0xccd7e58ef8bf4aa6
+; DWO-5: 0x00000047: DW_TAG_compile_unit
+
+
+; ModuleID = 't.cpp'
+source_filename = "t.cpp"
+target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
+target triple = "wasm32-unknown-unknown-wasm"
+
+%struct.S = type { i32 }
+
+ at s = global %struct.S zeroinitializer, align 4, !dbg !0
+
+!llvm.dbg.cu = !{!2}
+!llvm.module.flags = !{!10, !11}
+!llvm.ident = !{!12}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(name: "s", scope: !2, file: !3, line: 5, type: !6, isLocal: false, isDefinition: true)
+!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "clang version 5.0.0 (trunk 295942)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5)
+!3 = !DIFile(filename: "t.cpp", directory: "/home/probinson/projects/scratch")
+!4 = !{}
+!5 = !{!0}
+!6 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "S", file: !3, line: 1, size: 32, elements: !7, identifier: "_ZTS1S")
+!7 = !{!8}
+!8 = !DIDerivedType(tag: DW_TAG_member, name: "s1", scope: !6, file: !3, line: 2, baseType: !9, size: 32)
+!9 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!10 = !{i32 2, !"Dwarf Version", i32 4}
+!11 = !{i32 2, !"Debug Info Version", i32 3}
+!12 = !{!"clang version 5.0.0 (trunk 295942)"}
More information about the llvm-commits
mailing list