diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp --- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -1546,12 +1546,27 @@ ensureAbstractEntityIsCreatedIfScoped(TheCU, Var.first, Scope->getScopeNode()); - if (DbgVariable *DbgVar = MFVars.lookup(Var)) { - if (auto *MMI = std::get_if(DbgVar)) - MMI->addFrameIndexExpr(VI.Expr, VI.getStackSlot()); - else - DbgVar->get().addExpr(VI.getEntryValueRegister(), - *VI.Expr); + // If we have already seen information for this variable, add to what we + // already know. + if (DbgVariable *PreviousLoc = MFVars.lookup(Var)) { + auto *PreviousMMI = std::get_if(PreviousLoc); + auto *PreviousEntryValue = std::get_if(PreviousLoc); + // Previous and new locations are both stack slots (MMI). + if (PreviousMMI && VI.inStackSlot()) + PreviousMMI->addFrameIndexExpr(VI.Expr, VI.getStackSlot()); + // Previous and new locations are both entry values. + else if (PreviousEntryValue && VI.inEntryValueRegister()) + PreviousEntryValue->addExpr(VI.getEntryValueRegister(), *VI.Expr); + else { + // Locations differ, this should (rarely) happen in optimized async + // coroutines. + // Prefer whichever location has an EntryValue. + if (PreviousLoc->holds()) + PreviousLoc->emplace(VI.getEntryValueRegister(), + *VI.Expr); + LLVM_DEBUG(dbgs() << "Dropping debug info for " << VI.Var->getName() + << ", conflicting fragment location types\n"); + } continue; } diff --git a/llvm/test/DebugInfo/AArch64/dbg-entry-value-swiftasync.mir b/llvm/test/DebugInfo/AArch64/dbg-entry-value-swiftasync.mir --- a/llvm/test/DebugInfo/AArch64/dbg-entry-value-swiftasync.mir +++ b/llvm/test/DebugInfo/AArch64/dbg-entry-value-swiftasync.mir @@ -8,16 +8,23 @@ # CHECK-SAME: DW_OP_GNU_entry_value(DW_OP_reg22 W22), DW_OP_piece 0x8, # CHECK-SAME: DW_OP_GNU_entry_value(DW_OP_reg22 W22), DW_OP_plus_uconst 0x2a, DW_OP_piece 0x8) # CHECK-NEXT: DW_AT_name ("fragmented_var") +# CHECK: DW_TAG_variable +# CHECK-NEXT: DW_AT_location (DW_OP_piece 0x8, DW_OP_GNU_entry_value(DW_OP_reg22 W22), DW_OP_piece 0x8) +# CHECK-NEXT: DW_AT_name ("multi_type_fragmented_var") --- | target triple = "aarch64--" define void @foo(ptr %unused_arg, ptr swiftasync %async_arg) !dbg !4 { + %storage = alloca i64 call void @llvm.dbg.declare(metadata ptr %async_arg, metadata !10, metadata !DIExpression(DW_OP_LLVM_entry_value, 1)), !dbg !12 ; A two fragment variable. ; Fragments intentionally out of order to ensure the code can handle this. call void @llvm.dbg.declare(metadata ptr %async_arg, metadata !10, metadata !DIExpression(DW_OP_LLVM_entry_value, 1, DW_OP_plus_uconst, 42, DW_OP_LLVM_fragment, 64, 64)), !dbg !12 call void @llvm.dbg.declare(metadata ptr %async_arg, metadata !11, metadata !DIExpression(DW_OP_LLVM_entry_value, 1, DW_OP_LLVM_fragment, 0, 64)), !dbg !12 + ; A fragmented variable mixing entry values and stack slot locations. + call void @llvm.dbg.declare(metadata ptr %async_arg, metadata !13, metadata !DIExpression(DW_OP_LLVM_entry_value, 1, DW_OP_LLVM_fragment, 64, 64)), !dbg !12 + call void @llvm.dbg.declare(metadata ptr %storage, metadata !13, metadata !DIExpression(DW_OP_LLVM_fragment, 0, 64)), !dbg !12 ret void, !dbg !12 } declare void @llvm.dbg.declare(metadata, metadata, metadata) @@ -36,6 +43,7 @@ !10 = !DILocalVariable(name: "a", scope: !4, file: !1, line: 1, type: !7) !11 = !DILocalVariable(name: "fragmented_var", scope: !4, file: !1, line: 1, type: !7) !12 = !DILocation(line: 1, column: 37, scope: !4) + !13 = !DILocalVariable(name: "multi_type_fragmented_var", scope: !4, file: !1, line: 1, type: !7) ... --- name: foo @@ -45,6 +53,11 @@ stack: - { id: 0, name: '', type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default, callee-saved-register: '$lr', callee-saved-restored: true } + - { id: 1, name: '', type: default, offset: 0, size: 1, alignment: 8, + stack-id: default, callee-saved-register: '', callee-saved-restored: true, + debug-info-variable: '!13', debug-info-expression: '!DIExpression(DW_OP_LLVM_fragment, 0, 64)', + debug-info-location: '!12' } + entry_values: - { entry-value-register: '$x22', debug-info-variable: '!10', debug-info-expression: '!DIExpression(DW_OP_LLVM_entry_value, 1, DW_OP_deref)', debug-info-location: '!12' } @@ -52,6 +65,8 @@ debug-info-location: '!12' } - { entry-value-register: '$x22', debug-info-variable: '!11', debug-info-expression: '!DIExpression(DW_OP_LLVM_entry_value, 1, DW_OP_deref, DW_OP_LLVM_fragment, 0, 64)', debug-info-location: '!12' } + - { entry-value-register: '$x22', debug-info-variable: '!13', debug-info-expression: '!DIExpression(DW_OP_LLVM_entry_value, 1, DW_OP_deref, DW_OP_LLVM_fragment, 64, 64)', + debug-info-location: '!12' } body: | bb.0 (%ir-block.0): liveins: $x0, $x22, $lr