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Some of SIE's post-mortem analysis infrastructure currently makes use of .debug_aranges, so we'd like to ensure the section's presence in PlayStation binaries. The simplest way to do this is to force emission when the debugger tuning is set to SCE (which is in turn typically initialized from the target triple). This also simplifies the driver.

llvm/test/DebugInfo/debuglineinfo-path.ll has been marked as UNSUPPORTED on PlayStation. When aranges are emitted, the DWARF in the test case is such that relocations need to be applied to the aranges section in order for symbolization to work. An alternative approach would be to implement the application of relocations in DWARFDebugArangeSet. While experiments show that this can be made to work with a modest patch, the test cases would be rather contrived. Since I expect the only utility for such a change would be to make this test case pass for PlayStation targets, and few - if any - outside of PlayStation care about aranges, UNSUPPORTED would seem to be a more practical option.

This was originally commited as 22eb290 (#99629) and later reverted at 84658fb (#99711) due to test failures on SIE built bots. These failures shouldn't recur due to 3b24e5d (#99897) and the aforementioned change to debuglineinfo-path.ll.

SIE tracker: TOOLCHAIN-16951

Some of SIE's post-mortem analysis infrastructure currently makes use of
.debug_aranges, so we'd like to ensure the section's presence in
PlayStation binaries. The simplest way to do this is to force emission
when the debugger tuning is set to SCE (which is in turn typically
initialized from the target triple). This also simplifies the driver.

llvm/test/DebugInfo/debuglineinfo-path.ll has been marked as UNSUPPORTED
on PlayStation. When aranges are emitted, the DWARF in the test case is
such that relocations need to be applied to the aranges section in order
for symbolization to work. An alternative approach would be to implement
the application of relocations in DWARFDebugArangeSet. While experiments
show that this can be made to work with a modest patch, the test cases
would be rather contrived. Since I expect the only utility for such a
change would be to make this test case pass for PlayStation targets, and
few - if any - outside of PlayStation care about aranges, UNSUPPORTED
would seem to be a more practical option.

This was originally commited as 22eb290 (llvm#99629) and later reverted
at 84658fb (llvm#99711) due to test failures on SIE built bots. These
failures shouldn't recur due to 3b24e5d (llvm#99897) and the
aforementioned change to debuglineinfo-path.ll.

SIE tracker: TOOLCHAIN-16951
@playstation-edd playstation-edd requested review from jmorse and pogo59 July 23, 2024 16:50
@llvmbot llvmbot added clang Clang issues not falling into any other category clang:driver 'clang' and 'clang++' user-facing binaries. Not 'clang-cl' debuginfo labels Jul 23, 2024
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llvmbot commented Jul 23, 2024

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@llvm/pr-subscribers-debuginfo

@llvm/pr-subscribers-clang-driver

Author: Edd Dawson (playstation-edd)

Changes

Some of SIE's post-mortem analysis infrastructure currently makes use of .debug_aranges, so we'd like to ensure the section's presence in PlayStation binaries. The simplest way to do this is to force emission when the debugger tuning is set to SCE (which is in turn typically initialized from the target triple). This also simplifies the driver.

llvm/test/DebugInfo/debuglineinfo-path.ll has been marked as UNSUPPORTED on PlayStation. When aranges are emitted, the DWARF in the test case is such that relocations need to be applied to the aranges section in order for symbolization to work. An alternative approach would be to implement the application of relocations in DWARFDebugArangeSet. While experiments show that this can be made to work with a modest patch, the test cases would be rather contrived. Since I expect the only utility for such a change would be to make this test case pass for PlayStation targets, and few - if any - outside of PlayStation care about aranges, UNSUPPORTED would seem to be a more practical option.

This was originally commited as 22eb290 (#99629) and later reverted at 84658fb (#99711) due to test failures on SIE built bots. These failures shouldn't recur due to 3b24e5d (#99897) and the aforementioned change to debuglineinfo-path.ll.

SIE tracker: TOOLCHAIN-16951


Full diff: https://github.com/llvm/llvm-project/pull/100160.diff

9 Files Affected:

  • (modified) clang/lib/Driver/ToolChains/Clang.cpp (+2-5)
  • (modified) clang/lib/Driver/ToolChains/PS4CPU.cpp (-8)
  • (modified) clang/test/Driver/debug-options.c (+10-11)
  • (modified) clang/test/Driver/lto-jobs.c (+1-1)
  • (modified) clang/test/Driver/ps4-linker.c (+4-4)
  • (modified) llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp (+4-1)
  • (modified) llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h (+3)
  • (added) llvm/test/DebugInfo/X86/debug-aranges-sce-tuning.ll (+33)
  • (modified) llvm/test/DebugInfo/debuglineinfo-path.ll (+3-2)
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 78936fd634f33..136db416f5b30 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -4718,11 +4718,8 @@ renderDebugOptions(const ToolChain &TC, const Driver &D, const llvm::Triple &T,
 
   // -gdwarf-aranges turns on the emission of the aranges section in the
   // backend.
-  // Always enabled for SCE tuning.
-  bool NeedAranges = DebuggerTuning == llvm::DebuggerKind::SCE;
-  if (const Arg *A = Args.getLastArg(options::OPT_gdwarf_aranges))
-    NeedAranges = checkDebugInfoOption(A, Args, D, TC) || NeedAranges;
-  if (NeedAranges) {
+  if (const Arg *A = Args.getLastArg(options::OPT_gdwarf_aranges);
+      A && checkDebugInfoOption(A, Args, D, TC)) {
     CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-generate-arange-section");
   }
diff --git a/clang/lib/Driver/ToolChains/PS4CPU.cpp b/clang/lib/Driver/ToolChains/PS4CPU.cpp
index 974e486a0082b..d6af9388e54a6 100644
--- a/clang/lib/Driver/ToolChains/PS4CPU.cpp
+++ b/clang/lib/Driver/ToolChains/PS4CPU.cpp
@@ -162,10 +162,6 @@ void tools::PS4cpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   };
 
   if (UseLTO) {
-    // We default to creating the arange section, but LTO does not. Enable it
-    // here.
-    AddCodeGenFlag("-generate-arange-section");
-
     // This tells LTO to perform JustMyCode instrumentation.
     if (UseJMC)
       AddCodeGenFlag("-enable-jmc-instrument");
@@ -272,10 +268,6 @@ void tools::PS5cpu::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   };
 
   if (UseLTO) {
-    // We default to creating the arange section, but LTO does not. Enable it
-    // here.
-    AddCodeGenFlag("-generate-arange-section");
-
     // This tells LTO to perform JustMyCode instrumentation.
     if (UseJMC)
       AddCodeGenFlag("-enable-jmc-instrument");
diff --git a/clang/test/Driver/debug-options.c b/clang/test/Driver/debug-options.c
index 0a665f7017d63..21785ba01cb41 100644
--- a/clang/test/Driver/debug-options.c
+++ b/clang/test/Driver/debug-options.c
@@ -118,27 +118,28 @@
 // RUN: %clang_cl -### -c -Z7 -target x86_64-windows-msvc -- %s 2>&1 \
 // RUN:             | FileCheck -check-prefix=G_NOTUNING %s
 
-// On the PS4/PS5, -g defaults to -gno-column-info, and we always generate the
-// arange section.
+// On the PS4/PS5, -g defaults to -gno-column-info. We default to always
+// generating the arange section, but keyed off SCE DebuggerTuning being in
+// play during codegen, instead of -generate-arange-section.
 // RUN: %clang -### -c %s -target x86_64-scei-ps4 2>&1 \
 // RUN:             | FileCheck -check-prefix=NOG_PS %s
 // RUN: %clang -### -c %s -target x86_64-sie-ps5 2>&1 \
 // RUN:             | FileCheck -check-prefix=NOG_PS %s
 /// PS4 will stay on v4 even if the generic default version changes.
 // RUN: %clang -### -c %s -g -target x86_64-scei-ps4 2>&1 \
-// RUN:             | FileCheck -check-prefixes=G_DWARF4,GARANGE,G_SCE,NOCI,FWD_TMPL_PARAMS %s
+// RUN:             | FileCheck -check-prefixes=G_DWARF4,G_SCE,NOCI,FWD_TMPL_PARAMS %s
 // RUN: %clang -### -c %s -g -target x86_64-sie-ps5 2>&1 \
-// RUN:             | FileCheck -check-prefixes=G_DWARF5,GARANGE,G_SCE,NOCI,FWD_TMPL_PARAMS %s
+// RUN:             | FileCheck -check-prefixes=G_DWARF5,G_SCE,NOCI,FWD_TMPL_PARAMS %s
 // RUN: %clang -### -c %s -g -gcolumn-info -target x86_64-scei-ps4 2>&1 \
 // RUN:             | FileCheck -check-prefix=CI %s
 // RUN: %clang -### -c %s -gsce -target x86_64-unknown-linux 2>&1 \
 // RUN:             | FileCheck -check-prefix=NOCI %s
 // RUN: %clang -### %s -g -flto=thin -target x86_64-scei-ps4 2>&1 \
-// RUN:             | FileCheck -check-prefix=SNLDTLTOGARANGE %s
+// RUN:             | FileCheck -check-prefix=LDGARANGE %s
 // RUN: %clang -### %s -g -flto=full -target x86_64-scei-ps4 2>&1 \
-// RUN:             | FileCheck -check-prefix=SNLDFLTOGARANGE %s
+// RUN:             | FileCheck -check-prefix=LDGARANGE %s
 // RUN: %clang -### %s -g -flto -target x86_64-scei-ps5 2>&1 \
-// RUN:             | FileCheck -check-prefix=LLDGARANGE %s
+// RUN:             | FileCheck -check-prefix=LDGARANGE %s
 // RUN: %clang -### %s -g -target x86_64-scei-ps5 2>&1 \
 // RUN:             | FileCheck -check-prefix=LDGARANGE %s
 
@@ -321,8 +322,7 @@
 //
 // NOG_PS: "-cc1"
 // NOG_PS-NOT: "-dwarf-version=
-// NOG_PS: "-generate-arange-section"
-// NOG_PS-NOT: "-dwarf-version=
+// NOG_PS-NOT: "-generate-arange-section"
 //
 // G_ERR: error: unknown argument:
 //
@@ -402,8 +402,7 @@
 //
 
 // LDGARANGE: {{".*ld.*"}} {{.*}}
-// LDGARANGE-NOT: "-plugin-opt=-generate-arange-section"
-// LLDGARANGE: {{".*lld.*"}} {{.*}} "-plugin-opt=-generate-arange-section"
+// LDGARANGE-NOT: -generate-arange-section"
 // SNLDTLTOGARANGE: {{".*orbis-ld.*"}} {{.*}} "-lto-thin-debug-options= -generate-arange-section"
 // SNLDFLTOGARANGE: {{".*orbis-ld.*"}} {{.*}} "-lto-debug-options= -generate-arange-section"
 
diff --git a/clang/test/Driver/lto-jobs.c b/clang/test/Driver/lto-jobs.c
index 43a478b0664d8..b4f109e4c502c 100644
--- a/clang/test/Driver/lto-jobs.c
+++ b/clang/test/Driver/lto-jobs.c
@@ -11,7 +11,7 @@
 // RUN: %clang --target=x86_64-scei-ps4 -### %s -flto=thin -flto-jobs=5 2> %t
 // RUN: FileCheck -check-prefix=CHECK-PS4-LINK-THIN-JOBS-ACTION < %t %s
 //
-// CHECK-PS4-LINK-THIN-JOBS-ACTION: "-lto-thin-debug-options= -generate-arange-section -threads=5"
+// CHECK-PS4-LINK-THIN-JOBS-ACTION: "-lto-thin-debug-options= -threads=5"
 
 // RUN: %clang --target=x86_64-apple-darwin13.3.0 -### %s -flto=thin -flto-jobs=5 2> %t
 // RUN: FileCheck -check-prefix=CHECK-LINK-THIN-JOBS2-ACTION < %t %s
diff --git a/clang/test/Driver/ps4-linker.c b/clang/test/Driver/ps4-linker.c
index be0103bffe813..be989cdd7d5b1 100644
--- a/clang/test/Driver/ps4-linker.c
+++ b/clang/test/Driver/ps4-linker.c
@@ -5,8 +5,8 @@
 // RUN: %clang --target=x86_64-scei-ps4 -flto=full -fjmc %s -### 2>&1 | FileCheck --check-prefixes=CHECK-FULL-LTO,CHECK-LIB %s
 
 // CHECK-NOT: -enable-jmc-instrument
-// CHECK-THIN-LTO: "-lto-thin-debug-options= -generate-arange-section -enable-jmc-instrument"
-// CHECK-FULL-LTO: "-lto-debug-options= -generate-arange-section -enable-jmc-instrument"
+// CHECK-THIN-LTO: "-lto-thin-debug-options= -enable-jmc-instrument"
+// CHECK-FULL-LTO: "-lto-debug-options= -enable-jmc-instrument"
 
 // Check the default library name.
 // CHECK-LIB: "--whole-archive" "-lSceDbgJmc" "--no-whole-archive"
@@ -16,5 +16,5 @@
 // RUN: %clang --target=x86_64-scei-ps4 -flto=thin -fcrash-diagnostics-dir=mydumps %s -### 2>&1 | FileCheck --check-prefixes=CHECK-DIAG-THIN-LTO %s
 // RUN: %clang --target=x86_64-scei-ps4 -flto=full -fcrash-diagnostics-dir=mydumps %s -### 2>&1 | FileCheck --check-prefixes=CHECK-DIAG-FULL-LTO %s
 
-// CHECK-DIAG-THIN-LTO: "-lto-thin-debug-options= -generate-arange-section -crash-diagnostics-dir=mydumps"
-// CHECK-DIAG-FULL-LTO: "-lto-debug-options= -generate-arange-section -crash-diagnostics-dir=mydumps"
+// CHECK-DIAG-THIN-LTO: "-lto-thin-debug-options= -crash-diagnostics-dir=mydumps"
+// CHECK-DIAG-FULL-LTO: "-lto-debug-options= -crash-diagnostics-dir=mydumps"
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index f88653146cc6f..5f1f315c5ab24 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -354,6 +354,9 @@ DwarfDebug::DwarfDebug(AsmPrinter *A)
 
   UseLocSection = !TT.isNVPTX();
 
+  // Always emit .debug_aranges for SCE tuning.
+  UseARangesSection = GenerateARangeSection || tuneForSCE();
+
   HasAppleExtensionAttributes = tuneForLLDB();
 
   // Handle split DWARF.
@@ -1450,7 +1453,7 @@ void DwarfDebug::endModule() {
   emitDebugInfo();
 
   // Emit info into a debug aranges section.
-  if (GenerateARangeSection)
+  if (UseARangesSection)
     emitDebugARanges();
 
   // Emit info into a debug ranges section.
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 452485b632c45..13f4c379e0027 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -435,6 +435,9 @@ class DwarfDebug : public DebugHandlerBase {
   ///Allow emission of the .debug_loc section.
   bool UseLocSection = true;
 
+  /// Allow emission of .debug_aranges section
+  bool UseARangesSection = false;
+
   /// Generate DWARF v4 type units.
   bool GenerateTypeUnits;
 
diff --git a/llvm/test/DebugInfo/X86/debug-aranges-sce-tuning.ll b/llvm/test/DebugInfo/X86/debug-aranges-sce-tuning.ll
new file mode 100644
index 0000000000000..ac0d61aef2b1c
--- /dev/null
+++ b/llvm/test/DebugInfo/X86/debug-aranges-sce-tuning.ll
@@ -0,0 +1,33 @@
+; This checks that .debug_aranges is always generated for the SCE debugger
+; tuning.
+
+; RUN: llc -mtriple=x86_64 -debugger-tune=sce -filetype=obj %s -o %t
+; RUN: llvm-dwarfdump -debug-aranges %t | FileCheck %s
+
+; CHECK:      .debug_aranges contents:
+; CHECK-NEXT: Address Range Header:
+; CHECK-SAME:   length = 0x0000002c,
+
+; IR generated and reduced from:
+; $ cat foo.c
+; int foo;
+; $ clang -g -S -emit-llvm foo.c -o foo.ll
+
+target triple = "x86_64-unknown-linux-gnu"
+
+@foo = dso_local global i32 0, align 4, !dbg !0
+
+!llvm.dbg.cu = !{!2}
+!llvm.module.flags = !{!6, !7, !8}
+!llvm.ident = !{!9}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(name: "foo", scope: !2, file: !3, line: 1, type: !5, isLocal: false, isDefinition: true)
+!2 = distinct !DICompileUnit(language: DW_LANG_C11, file: !3, producer: "clang version 19.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, globals: !4, splitDebugInlining: false, nameTableKind: None)
+!3 = !DIFile(filename: "foo.c", directory: "/tmp")
+!4 = !{!0}
+!5 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!6 = !{i32 7, !"Dwarf Version", i32 5}
+!7 = !{i32 2, !"Debug Info Version", i32 3}
+!8 = !{i32 1, !"wchar_size", i32 4}
+!9 = !{!"clang version 19.0.0"}
diff --git a/llvm/test/DebugInfo/debuglineinfo-path.ll b/llvm/test/DebugInfo/debuglineinfo-path.ll
index f6574a2a46f12..7e408aff6ceff 100644
--- a/llvm/test/DebugInfo/debuglineinfo-path.ll
+++ b/llvm/test/DebugInfo/debuglineinfo-path.ll
@@ -1,8 +1,9 @@
 ; Make sure that absolute source dir is detected correctly regardless of the platform.
 
 ; On powerpc llvm-nm describes win_func as a global variable, not a function. It breaks the test.
-; It is not essential to DWARF path handling code we're testing here.
-; UNSUPPORTED: target=powerpc{{.*}}
+; On PlayStation, (pre-relocated) .debug_aranges cause symbolization to fail, also breaking the test.
+; These are not essential to DWARF path handling code we're testing here.
+; UNSUPPORTED: target=powerpc{{.*}}, target=x86_64-{{.*-ps[45]}}
 ; REQUIRES: object-emission
 ; RUN: %llc_dwarf -O0 -filetype=obj -o %t < %s
 ; RUN: llvm-nm --radix=o %t | grep posix_absolute_func > %t.posix_absolute_func

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One nit on the test, otherwise LGTM.

; int foo;
; $ clang -g -S -emit-llvm foo.c -o foo.ll

target triple = "x86_64-unknown-linux-gnu"
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This is redundant with the explicit triple on the llc command line.

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@MaskRay MaskRay Jul 23, 2024

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clang --target=x86_64-linux-gnu above and the the target triple in IR might be slightly useful to omit -mtriple for llc : requires less typing for a user invoking llc directly, possibly to debug some stuff.

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I think I've done this - if I got your meaning(?)

@@ -0,0 +1,33 @@
; This checks that .debug_aranges is always generated for the SCE debugger
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The https://llvm.org/docs/TestingGuide.html#elaborated-tests style could make test update easier in the future.

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Done!

@playstation-edd playstation-edd merged commit 3993a47 into llvm:main Jul 24, 2024
7 checks passed
@playstation-edd playstation-edd deleted the sce-tuning-aranges-attempt-2 branch July 24, 2024 08:07
yuxuanchen1997 pushed a commit that referenced this pull request Jul 25, 2024
…100160)

Summary:
Some of SIE's post-mortem analysis infrastructure currently makes use of
.debug_aranges, so we'd like to ensure the section's presence in
PlayStation binaries. The simplest way to do this is to force emission
when the debugger tuning is set to SCE (which is in turn typically
initialized from the target triple). This also simplifies the driver.

llvm/test/DebugInfo/debuglineinfo-path.ll has been marked as UNSUPPORTED
on PlayStation. When aranges are emitted, the DWARF in the test case is
such that relocations need to be applied to the aranges section in order
for symbolization to work. An alternative approach would be to implement
the application of relocations in DWARFDebugArangeSet. While experiments
show that this can be made to work with a modest patch, the test cases
would be rather contrived. Since I expect the only utility for such a
change would be to make this test case pass for PlayStation targets, and
few - if any - outside of PlayStation care about aranges, UNSUPPORTED
would seem to be a more practical option.

This was originally commited as 22eb290 (#99629) and later reverted
at 84658fb (#99711) due to test failures on SIE built bots. These
failures shouldn't recur due to 3b24e5d (#99897) and the
aforementioned change to debuglineinfo-path.ll.

SIE tracker: TOOLCHAIN-16951

Test Plan: 

Reviewers: 

Subscribers: 

Tasks: 

Tags: 


Differential Revision: https://phabricator.intern.facebook.com/D60250743
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