diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp index e884f452f03..d1000dc9a9f 100644 --- a/lib/Linker/LinkModules.cpp +++ b/lib/Linker/LinkModules.cpp @@ -1250,10 +1250,9 @@ void ModuleLinker::linkNamedMDNodes() { /// Drop DISubprograms that have been superseded. /// -/// FIXME: this creates an asymmetric result: we strip functions from losing -/// subprograms in DstM, but leave losing subprograms in SrcM. -/// TODO: Remove this logic once the backend can correctly determine canonical -/// subprograms. +/// FIXME: this creates an asymmetric result: we strip losing subprograms from +/// DstM, but leave losing subprograms in SrcM. Instead we should also strip +/// losers from SrcM, but this requires extra plumbing in MapMetadata. void ModuleLinker::stripReplacedSubprograms() { // Avoid quadratic runtime by returning early when there's nothing to do. if (OverridingFunctions.empty()) @@ -1263,8 +1262,8 @@ void ModuleLinker::stripReplacedSubprograms() { auto Functions = std::move(OverridingFunctions); OverridingFunctions.clear(); - // Drop functions from subprograms if they've been overridden by the new - // compile unit. + // Drop subprograms whose functions have been overridden by the new compile + // unit. NamedMDNode *CompileUnits = DstM->getNamedMetadata("llvm.dbg.cu"); if (!CompileUnits) return; @@ -1275,15 +1274,19 @@ void ModuleLinker::stripReplacedSubprograms() { DITypedArray SPs(CU.getSubprograms()); assert(SPs && "Expected valid subprogram array"); + SmallVector NewSPs; + NewSPs.reserve(SPs.getNumElements()); for (unsigned S = 0, SE = SPs.getNumElements(); S != SE; ++S) { DISubprogram SP = SPs.getElement(S); - if (!SP || !SP.getFunction() || !Functions.count(SP.getFunction())) + if (SP && SP.getFunction() && Functions.count(SP.getFunction())) continue; - // Prevent DebugInfoFinder from tagging this as the canonical subprogram, - // since the canonical one is in the incoming module. - SP->replaceFunction(nullptr); + NewSPs.push_back(SP); } + + // Redirect operand to the overriding subprogram. + if (NewSPs.size() != SPs.getNumElements()) + CU.replaceSubprograms(DIArray(MDNode::get(DstM->getContext(), NewSPs))); } } diff --git a/test/Linker/Inputs/subprogram-linkonce-weak.ll b/test/Linker/Inputs/subprogram-linkonce-weak.ll deleted file mode 100644 index e73143dae8c..00000000000 --- a/test/Linker/Inputs/subprogram-linkonce-weak.ll +++ /dev/null @@ -1,16 +0,0 @@ -define weak i32 @foo(i32 %a, i32 %b) { -entry: - %sum = call i32 @fastadd(i32 %a, i32 %b), !dbg !MDLocation(line: 52, scope: !3) - ret i32 %sum, !dbg !MDLocation(line: 53, scope: !3) -} - -declare i32 @fastadd(i32, i32) - -!llvm.module.flags = !{!0} -!0 = !{i32 2, !"Debug Info Version", i32 3} - -!llvm.dbg.cu = !{!1} -!1 = !MDCompileUnit(language: DW_LANG_C99, file: !2, subprograms: !{!3}, emissionKind: 1) -!2 = !MDFile(filename: "foo.c", directory: "/path/to/dir") -!3 = !MDSubprogram(file: !2, scope: !2, line: 51, name: "foo", function: i32 (i32, i32)* @foo, type: !4) -!4 = !MDSubroutineType(types: !{}) diff --git a/test/Linker/replaced-function-matches-first-subprogram.ll b/test/Linker/replaced-function-matches-first-subprogram.ll index ac6633d1c01..508e28da565 100644 --- a/test/Linker/replaced-function-matches-first-subprogram.ll +++ b/test/Linker/replaced-function-matches-first-subprogram.ll @@ -45,9 +45,9 @@ entry: !1 = !MDFile(filename: "t1.cpp", directory: "/Users/dexonsmith/data/llvm/staging/test/Linker/repro/d1") !2 = !{} -; Extract out each compile unit's single subprogram. The replaced subprogram's -; function should drop to null in the first compile unit. -; CHECK-DAG: ![[SPs1]] = !{![[SP1:[0-9]+]], ![[SP2r:[0-9]+]]} +; Extract out each compile unit's single subprogram. The replaced subprogram +; should be dropped by the first compile unit. +; CHECK-DAG: ![[SPs1]] = !{![[SP1:[0-9]+]]} ; CHECK-DAG: ![[SPs2]] = !{![[SP2:[0-9]+]]} !3 = !{!4, !7} !4 = !MDSubprogram(name: "foo", line: 2, isLocal: false, isDefinition: true, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 2, file: !1, scope: !5, type: !6, function: i32 ()* @_Z3foov, variables: !2) @@ -58,10 +58,6 @@ entry: ; subprogram is pointing at the correct function. ; CHECK-DAG: ![[SP1]] = !MDSubprogram({{.*}} function: i32 ()* @_Z3foov ; CHECK-DAG: ![[SP2]] = !MDSubprogram({{.*}} file: ![[FILE:[0-9]+]],{{.*}} function: i32 (%struct.Class*)* @_ZN5ClassIiE3fooEv - -; We can't use CHECK-NOT/CHECK-SAME with a CHECK-DAG, so rely on field order to -; prove that there's no function: here. -; CHECK-DAG: ![[SP2r]] = {{.*}}!MDSubprogram({{.*}} isOptimized: false, variables: !7 = !MDSubprogram(name: "foo", line: 2, isLocal: false, isDefinition: true, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 2, file: !8, scope: !9, type: !6, function: i32 (%struct.Class*)* @_ZN5ClassIiE3fooEv, variables: !2) ; The new subprogram should be pointing at the new directory. diff --git a/test/Linker/subprogram-linkonce-weak.ll b/test/Linker/subprogram-linkonce-weak.ll deleted file mode 100644 index 42a8b39208b..00000000000 --- a/test/Linker/subprogram-linkonce-weak.ll +++ /dev/null @@ -1,171 +0,0 @@ -; RUN: llvm-link %s %S/Inputs/subprogram-linkonce-weak.ll -S -o %t1 -; RUN: FileCheck %s -check-prefix=LW -check-prefix=CHECK <%t1 -; RUN: llvm-link %S/Inputs/subprogram-linkonce-weak.ll %s -S -o %t2 -; RUN: FileCheck %s -check-prefix=WL -check-prefix=CHECK <%t2 - -; This testcase tests the following flow: -; - File A defines a linkonce version of @foo which has inlined into @bar. -; - File B defines a weak version of @foo (different definition). -; - Linkage rules state File B version of @foo wins. -; - @bar still has inlined debug info related to the linkonce @foo. -; -; This should fix PR22792, although the testcase was hand-written. There's a -; RUN line with a crasher for llc at the end with checks for the DWARF output. - -; The LW prefix means linkonce (this file) first, then weak (the other file). -; The WL prefix means weak (the other file) first, then linkonce (this file). - -; We'll see @bar before @foo if this file is first. -; LW-LABEL: define i32 @bar( -; LW: %sum = add i32 %a, %b, !dbg ![[FOOINBAR:[0-9]+]] -; LW: ret i32 %sum, !dbg ![[BARRET:[0-9]+]] -; LW-LABEL: define weak i32 @foo( -; LW: %sum = call i32 @fastadd(i32 %a, i32 %b), !dbg ![[FOOCALL:[0-9]+]] -; LW: ret i32 %sum, !dbg ![[FOORET:[0-9]+]] - -; We'll see @foo before @bar if this file is second. -; WL-LABEL: define weak i32 @foo( -; WL: %sum = call i32 @fastadd(i32 %a, i32 %b), !dbg ![[FOOCALL:[0-9]+]] -; WL: ret i32 %sum, !dbg ![[FOORET:[0-9]+]] -; WL-LABEL: define i32 @bar( -; WL: %sum = add i32 %a, %b, !dbg ![[FOOINBAR:[0-9]+]] -; WL: ret i32 %sum, !dbg ![[BARRET:[0-9]+]] - -define i32 @bar(i32 %a, i32 %b) { -entry: - %sum = add i32 %a, %b, !dbg !MDLocation(line: 2, scope: !4, - inlinedAt: !MDLocation(line: 12, scope: !3)) - ret i32 %sum, !dbg !MDLocation(line: 13, scope: !3) -} - -define linkonce i32 @foo(i32 %a, i32 %b) { -entry: - %sum = add i32 %a, %b, !dbg !MDLocation(line: 2, scope: !4) - ret i32 %sum, !dbg !MDLocation(line: 3, scope: !4) -} - -!llvm.module.flags = !{!0} -!0 = !{i32 2, !"Debug Info Version", i32 3} - -; CHECK-LABEL: !llvm.dbg.cu = -; LW-SAME: !{![[LCU:[0-9]+]], ![[WCU:[0-9]+]]} -; WL-SAME: !{![[WCU:[0-9]+]], ![[LCU:[0-9]+]]} -!llvm.dbg.cu = !{!1} - -; LW: ![[LCU]] = !MDCompileUnit({{.*}} subprograms: ![[LSPs:[0-9]+]] -; LW: ![[LSPs]] = !{![[BARSP:[0-9]+]], ![[FOOSP:[0-9]+]]} -; LW: ![[BARSP]] = !MDSubprogram(name: "bar", -; LW-SAME: function: i32 (i32, i32)* @bar -; LW: ![[FOOSP]] = {{.*}}!MDSubprogram(name: "foo", -; LW-NOT: function: -; LW-SAME: ){{$}} -; LW: ![[WCU]] = !MDCompileUnit({{.*}} subprograms: ![[WSPs:[0-9]+]] -; LW: ![[WSPs]] = !{![[WEAKFOOSP:[0-9]+]]} -; LW: ![[WEAKFOOSP]] = !MDSubprogram(name: "foo", -; LW-SAME: function: i32 (i32, i32)* @foo -; LW: ![[FOOINBAR]] = !MDLocation(line: 2, scope: ![[FOOSP]], inlinedAt: ![[BARIA:[0-9]+]]) -; LW: ![[BARIA]] = !MDLocation(line: 12, scope: ![[BARSP]]) -; LW: ![[BARRET]] = !MDLocation(line: 13, scope: ![[BARSP]]) -; LW: ![[FOOCALL]] = !MDLocation(line: 52, scope: ![[WEAKFOOSP]]) -; LW: ![[FOORET]] = !MDLocation(line: 53, scope: ![[WEAKFOOSP]]) - -; Same as above, but reordered. -; WL: ![[WCU]] = !MDCompileUnit({{.*}} subprograms: ![[WSPs:[0-9]+]] -; WL: ![[WSPs]] = !{![[WEAKFOOSP:[0-9]+]]} -; WL: ![[WEAKFOOSP]] = !MDSubprogram(name: "foo", -; WL-SAME: function: i32 (i32, i32)* @foo -; WL: ![[LCU]] = !MDCompileUnit({{.*}} subprograms: ![[LSPs:[0-9]+]] -; WL: ![[LSPs]] = !{![[BARSP:[0-9]+]], ![[FOOSP:[0-9]+]]} -; WL: ![[BARSP]] = !MDSubprogram(name: "bar", -; WL-SAME: function: i32 (i32, i32)* @bar -; WL: ![[FOOSP]] = {{.*}}!MDSubprogram(name: "foo", -; Note, for symmetry, this should be "NOT: function:" and "SAME: ){{$}}". -; WL-SAME: function: i32 (i32, i32)* @foo -; WL: ![[FOOCALL]] = !MDLocation(line: 52, scope: ![[WEAKFOOSP]]) -; WL: ![[FOORET]] = !MDLocation(line: 53, scope: ![[WEAKFOOSP]]) -; WL: ![[FOOINBAR]] = !MDLocation(line: 2, scope: ![[FOOSP]], inlinedAt: ![[BARIA:[0-9]+]]) -; WL: ![[BARIA]] = !MDLocation(line: 12, scope: ![[BARSP]]) -; WL: ![[BARRET]] = !MDLocation(line: 13, scope: ![[BARSP]]) - -!1 = !MDCompileUnit(language: DW_LANG_C99, file: !2, subprograms: !{!3, !4}, emissionKind: 1) -!2 = !MDFile(filename: "bar.c", directory: "/path/to/dir") -!3 = !MDSubprogram(file: !2, scope: !2, line: 11, name: "bar", function: i32 (i32, i32)* @bar, type: !5) -!4 = !MDSubprogram(file: !2, scope: !2, line: 1, name: "foo", function: i32 (i32, i32)* @foo, type: !5) -!5 = !MDSubroutineType(types: !{}) - -; Crasher for llc. -; REQUIRES: object-emission -; RUN: %llc_dwarf -filetype=obj -O0 %t1 -o %t1.o -; RUN: llvm-dwarfdump %t1.o -debug-dump=all | FileCheck %s -check-prefix=DWLW -check-prefix=DW -; RUN: %llc_dwarf -filetype=obj -O0 %t2 -o %t2.o -; RUN: llvm-dwarfdump %t2.o -debug-dump=all | FileCheck %s -check-prefix=DWWL -check-prefix=DW -; Check that the debug info for the discarded linkonce version of @foo doesn't -; reference any code, and that the other subprograms look correct. - -; DW-LABEL: .debug_info contents: -; DWLW: DW_TAG_compile_unit -; DWLW: DW_AT_name {{.*}}"bar.c" -; DWLW: DW_TAG_subprogram -; DWLW-NOT: DW_AT_low_pc -; DWLW-NOT: DW_AT_high_pc -; DWLW: DW_AT_name {{.*}}foo -; DWLW: DW_AT_decl_file {{.*}}"/path/to/dir/bar.c" -; DWLW: DW_AT_decl_line {{.*}}(1) -; DWLW: DW_TAG_subprogram -; DWLW: DW_AT_low_pc -; DWLW: DW_AT_high_pc -; DWLW: DW_AT_name {{.*}}bar -; DWLW: DW_AT_decl_file {{.*}}"/path/to/dir/bar.c" -; DWLW: DW_AT_decl_line {{.*}}(11) - -; DWLW: DW_TAG_inlined_subroutine -; DWLW: DW_AT_abstract_origin -; DWLW: DW_TAG_compile_unit -; DWLW: DW_AT_name {{.*}}"foo.c" -; DWLW: DW_TAG_subprogram -; DWLW: DW_AT_low_pc -; DWLW: DW_AT_high_pc -; DWLW: DW_AT_name {{.*}}foo -; DWLW: DW_AT_decl_file {{.*}}"/path/to/dir/foo.c" -; DWLW: DW_AT_decl_line {{.*}}(51) - -; The DWARF output is already symmetric (just reordered). -; DWWL: DW_TAG_compile_unit -; DWWL: DW_AT_name {{.*}}"foo.c" -; DWWL: DW_TAG_subprogram -; DWWL: DW_AT_low_pc -; DWWL: DW_AT_high_pc -; DWWL: DW_AT_name {{.*}}foo -; DWWL: DW_AT_decl_file {{.*}}"/path/to/dir/foo.c" -; DWWL: DW_AT_decl_line {{.*}}(51) -; DWWL: DW_TAG_compile_unit -; DWWL: DW_AT_name {{.*}}"bar.c" -; DWWL: DW_TAG_subprogram -; DWWL-NOT: DW_AT_low_pc -; DWWL-NOT: DW_AT_high_pc -; DWWL: DW_AT_name {{.*}}foo -; DWWL: DW_AT_decl_file {{.*}}"/path/to/dir/bar.c" -; DWWL: DW_AT_decl_line {{.*}}(1) -; DWWL: DW_TAG_subprogram -; DWWL: DW_AT_low_pc -; DWWL: DW_AT_high_pc -; DWWL: DW_AT_name {{.*}}bar -; DWWL: DW_AT_decl_file {{.*}}"/path/to/dir/bar.c" -; DWWL: DW_AT_decl_line {{.*}}(11) -; DWWL: DW_TAG_inlined_subroutine -; DWWL: DW_AT_abstract_origin - -; DW-LABEL: .debug_line contents: -; Check that we have the right things in the line table as well. - -; DWLW-LABEL: file_names[{{ *}}1]{{.*}} bar.c -; DWLW: 2 0 1 0 0 is_stmt prologue_end -; DWLW-LABEL: file_names[{{ *}}1]{{.*}} foo.c -; DWLW: 52 0 1 0 0 is_stmt prologue_end -; DWLW-NOT: prologue_end - -; DWWL-LABEL: file_names[{{ *}}1]{{.*}} foo.c -; DWWL: 52 0 1 0 0 is_stmt prologue_end -; DWWL-LABEL: file_names[{{ *}}1]{{.*}} bar.c -; DWWL: 2 0 1 0 0 is_stmt prologue_end -; DWWL-NOT: prologue_end