From: David Blaikie Date: Thu, 30 Oct 2014 20:20:11 +0000 (+0000) Subject: PR21408: Workaround the appearance of duplicate variables due to problems when inlini... X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=commitdiff_plain;h=5f5c65058ba410d96a5087349a207a7d12e4c9f5 PR21408: Workaround the appearance of duplicate variables due to problems when inlining two calls to the same function from the same call site. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220923 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/AsmPrinter/DwarfFile.cpp b/lib/CodeGen/AsmPrinter/DwarfFile.cpp index 3d49db3db7e..c1c50df9ad3 100644 --- a/lib/CodeGen/AsmPrinter/DwarfFile.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfFile.cpp @@ -177,7 +177,12 @@ void DwarfFile::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { // A later indexed parameter has been found, insert immediately before it. if (CurNum > ArgNum) break; - assert(CurNum != ArgNum); + // FIXME: There are still some cases where two inlined functions are + // conflated together (two calls to the same function at the same + // location (eg: via a macro, or without column info, etc)) and then + // their arguments are conflated as well. + assert((LS->getParent() || CurNum != ArgNum) && + "Missing parameter for top level (non-inlined) function"); ++I; } Vars.insert(I, Var); diff --git a/test/DebugInfo/duplicate_inline.ll b/test/DebugInfo/duplicate_inline.ll new file mode 100644 index 00000000000..008b52f7ba7 --- /dev/null +++ b/test/DebugInfo/duplicate_inline.ll @@ -0,0 +1,117 @@ +; REQUIRES: object-emission + +; RUN: %llc_dwarf < %s -filetype=obj | llvm-dwarfdump -debug-dump=info - | FileCheck %s + +; Built with clang from the following source: +; void f1(int); +; __attribute__((always_inline)) inline void f2(int i) { f1(i); } +; +; #define MULTICALL \ +; f2(x); \ +; f2(y); +; +; void f3(int x, int y) { MULTICALL; } + +; FIXME: This produces only one inlined_subroutine, with two formal_parameters +; (both named "this"), one for each of the actual inlined subroutines. ; +; Inlined scopes are differentiated by the combination of 'inlined at' (call) +; location and the location within the function. If two calls to the same +; function occur at the same location the scopes end up conflated and there +; appears to be only one inlined function. +; To fix this, we'd need to add some kind of unique metadata per call site, possibly something like: +; +; !42 = metadata !{i32 1, i32 0, metadata !43, metadata !44} +; !44 = metadata !{i32 2, i32 0, metadata !45, null} +; +; -> +; +; !42 = metadata !{i32 1, i32 0, metadata !43, metadata !44} +; !44 = metadata !{metadata !45, metadata !44} +; !45 = metadata !{i32 2, i32 0, metadata !45, null} +; +; since cycles in metadata are not uniqued, the !44 node would not be shared +; between calls to the same function from the same location, ensuring separate +; inlined subroutines would be generated. +; +; Once this is done, the (insufficient) hack in clang that adds column +; information to call sites to differentiate inlined callers can be removed as it +; will no longer be necessary. +; +; While it might be nice to omit the duplicate parameter in this case (while +; we wait/work on the real fix), it's actually better to leave it in because it +; allows us to hold the invariant that every DbgVariable has a DIE, every time. +; This has proved valuable in finding other bugs, so I want to avoid removing the +; invariant/assertion. Besides, we don't know which one's the right one anyway... + +; CHECK: DW_TAG_subprogram +; CHECK: DW_TAG_inlined_subroutine +; CHECK: DW_TAG_formal_parameter +; CHECK-NOT: DW_TAG +; CHECK: DW_TAG_formal_parameter +; CHECK-NOT: DW_TAG +; CHECK: NULL +; CHECK-NOT: DW_TAG +; CHECK: NULL + +; Function Attrs: uwtable +define void @_Z2f3ii(i32 %x, i32 %y) #0 { +entry: + %i.addr.i1 = alloca i32, align 4 + %i.addr.i = alloca i32, align 4 + %x.addr = alloca i32, align 4 + %y.addr = alloca i32, align 4 + store i32 %x, i32* %x.addr, align 4 + call void @llvm.dbg.declare(metadata !{i32* %x.addr}, metadata !15, metadata !16), !dbg !17 + store i32 %y, i32* %y.addr, align 4 + call void @llvm.dbg.declare(metadata !{i32* %y.addr}, metadata !18, metadata !16), !dbg !19 + %0 = load i32* %x.addr, align 4, !dbg !20 + store i32 %0, i32* %i.addr.i, align 4, !dbg !20 + call void @llvm.dbg.declare(metadata !{i32* %i.addr.i}, metadata !21, metadata !16), !dbg !22 + %1 = load i32* %i.addr.i, align 4, !dbg !23 + call void @_Z2f1i(i32 %1), !dbg !23 + %2 = load i32* %y.addr, align 4, !dbg !20 + store i32 %2, i32* %i.addr.i1, align 4, !dbg !20 + call void @llvm.dbg.declare(metadata !{i32* %i.addr.i1}, metadata !21, metadata !16), !dbg !22 + %3 = load i32* %i.addr.i1, align 4, !dbg !23 + call void @_Z2f1i(i32 %3), !dbg !23 + ret void, !dbg !24 +} + +; Function Attrs: nounwind readnone +declare void @llvm.dbg.declare(metadata, metadata, metadata) #1 + +declare void @_Z2f1i(i32) #2 + +attributes #0 = { uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } +attributes #1 = { nounwind readnone } +attributes #2 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!12, !13} +!llvm.ident = !{!14} + +!0 = metadata !{metadata !"0x11\004\00clang version 3.6.0 \000\00\000\00\001", metadata !1, metadata !2, metadata !2, metadata !3, metadata !2, metadata !2} ; [ DW_TAG_compile_unit ] [/tmp/dbginfo/duplicate_inline.cpp] [DW_LANG_C_plus_plus] +!1 = metadata !{metadata !"duplicate_inline.cpp", metadata !"/tmp/dbginfo"} +!2 = metadata !{} +!3 = metadata !{metadata !4, metadata !9} +!4 = metadata !{metadata !"0x2e\00f3\00f3\00_Z2f3ii\008\000\001\000\000\00256\000\008", metadata !1, metadata !5, metadata !6, null, void (i32, i32)* @_Z2f3ii, null, null, metadata !2} ; [ DW_TAG_subprogram ] [line 8] [def] [f3] +!5 = metadata !{metadata !"0x29", metadata !1} ; [ DW_TAG_file_type ] [/tmp/dbginfo/duplicate_inline.cpp] +!6 = metadata !{metadata !"0x15\00\000\000\000\000\000\000", null, null, null, metadata !7, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ] +!7 = metadata !{null, metadata !8, metadata !8} +!8 = metadata !{metadata !"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed] +!9 = metadata !{metadata !"0x2e\00f2\00f2\00_Z2f2i\002\000\001\000\000\00256\000\002", metadata !1, metadata !5, metadata !10, null, null, null, null, metadata !2} ; [ DW_TAG_subprogram ] [line 2] [def] [f2] +!10 = metadata !{metadata !"0x15\00\000\000\000\000\000\000", null, null, null, metadata !11, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ] +!11 = metadata !{null, metadata !8} +!12 = metadata !{i32 2, metadata !"Dwarf Version", i32 4} +!13 = metadata !{i32 2, metadata !"Debug Info Version", i32 2} +!14 = metadata !{metadata !"clang version 3.6.0 "} +!15 = metadata !{metadata !"0x101\00x\0016777224\000", metadata !4, metadata !5, metadata !8} ; [ DW_TAG_arg_variable ] [x] [line 8] +!16 = metadata !{metadata !"0x102"} ; [ DW_TAG_expression ] +!17 = metadata !{i32 8, i32 13, metadata !4, null} +!18 = metadata !{metadata !"0x101\00y\0033554440\000", metadata !4, metadata !5, metadata !8} ; [ DW_TAG_arg_variable ] [y] [line 8] +!19 = metadata !{i32 8, i32 20, metadata !4, null} +!20 = metadata !{i32 8, i32 25, metadata !4, null} +!21 = metadata !{metadata !"0x101\00i\0016777218\000", metadata !9, metadata !5, metadata !8} ; [ DW_TAG_arg_variable ] [i] [line 2] +!22 = metadata !{i32 2, i32 51, metadata !9, metadata !20} +!23 = metadata !{i32 2, i32 56, metadata !9, metadata !20} +!24 = metadata !{i32 8, i32 36, metadata !4, null}