Index: llvm/trunk/lib/Transforms/Utils/Local.cpp =================================================================== --- llvm/trunk/lib/Transforms/Utils/Local.cpp +++ llvm/trunk/lib/Transforms/Utils/Local.cpp @@ -1052,9 +1052,31 @@ ExtendedArg = dyn_cast(ZExt->getOperand(0)); if (SExtInst *SExt = dyn_cast(SI->getOperand(0))) ExtendedArg = dyn_cast(SExt->getOperand(0)); - if (ExtendedArg) - Builder.insertDbgValueIntrinsic(ExtendedArg, 0, DIVar, DIExpr, + if (ExtendedArg) { + // We're now only describing a subset of the variable. The piece we're + // describing will always be smaller than the variable size, because + // VariableSize == Size of Alloca described by DDI. Since SI stores + // to the alloca described by DDI, if it's first operand is an extend, + // we're guaranteed that before extension, the value was narrower than + // the size of the alloca, hence the size of the described variable. + SmallVector NewDIExpr; + unsigned PieceOffset = 0; + // If this already is a bit piece, we drop the bit piece from the expression + // and record the offset. + if (DIExpr->isBitPiece()) { + NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end()-3); + PieceOffset = DIExpr->getBitPieceOffset(); + } else { + NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end()); + } + NewDIExpr.push_back(dwarf::DW_OP_bit_piece); + NewDIExpr.push_back(PieceOffset); //Offset + const DataLayout &DL = DDI->getModule()->getDataLayout(); + NewDIExpr.push_back(DL.getTypeSizeInBits(ExtendedArg->getType())); // Size + Builder.insertDbgValueIntrinsic(ExtendedArg, 0, DIVar, + Builder.createExpression(NewDIExpr), DDI->getDebugLoc(), SI); + } else Builder.insertDbgValueIntrinsic(SI->getOperand(0), 0, DIVar, DIExpr, DDI->getDebugLoc(), SI); Index: llvm/trunk/test/Transforms/Util/split-bit-piece.ll =================================================================== --- llvm/trunk/test/Transforms/Util/split-bit-piece.ll +++ llvm/trunk/test/Transforms/Util/split-bit-piece.ll @@ -0,0 +1,45 @@ +; Checks that llvm.dbg.declare -> llvm.dbg.value conversion utility +; (here exposed through the SROA) pass, properly inserts bit_piece expressions +; if it only describes part of the variable. +; RUN: opt -S -sroa %s | FileCheck %s + +; Function Attrs: nounwind readnone +declare void @llvm.dbg.declare(metadata, metadata, metadata) #0 + +; Function Attrs: nounwind uwtable +define hidden void @_ZN6__tsan9FastState14SetHistorySizeEi(i32 %hs) #1 align 2 { +entry: + %hs.addr = alloca i32, align 4 + %v1 = alloca i64, align 8 + %v2 = alloca i64, align 8 + store i32 %hs, i32* %hs.addr, align 4 +; CHECK: call void @llvm.dbg.value(metadata i32 %hs, i64 0, metadata !{{[0-9]+}}, metadata ![[EXPR:[0-9]+]]) +; CHECK: ![[EXPR]] = !DIExpression(DW_OP_bit_piece, 0 + call void @llvm.dbg.declare(metadata i64* %v1, metadata !9, metadata !12), !dbg !13 + %0 = load i32, i32* %hs.addr, align 4 + %conv = sext i32 %0 to i64 + store i64 %conv, i64* %v1, align 8 + %1 = load i64, i64* %v2, align 8 + unreachable +} + +attributes #0 = { nounwind readnone } + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!7} +!llvm.ident = !{!8} + +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.8.0 (trunk 256979) (llvm/trunk 257107)", isOptimized: false, runtimeVersion: 0, emissionKind: 1, retainedTypes: !2) +!1 = !DIFile(filename: "tsan_shadow_test.cc", directory: "/tmp") +!2 = !{!3, !5} +!3 = !DICompositeType(tag: DW_TAG_class_type, name: "FastState", file: !4, line: 91, size: 64, align: 64, identifier: "_ZTSN6__tsan9FastStateE") +!4 = !DIFile(filename: "/mnt/extra/llvm/projects/compiler-rt/lib/tsan/rtl/tsan_rtl.h", directory: "/tmp") +!5 = distinct !DIDerivedType(tag: DW_TAG_typedef, name: "u64", line: 78, baseType: !6) +!6 = !DIBasicType(name: "long long unsigned int", size: 64, align: 64, encoding: DW_ATE_unsigned) +!7 = !{i32 2, !"Debug Info Version", i32 3} +!8 = !{!"clang version 3.8.0 (trunk 256979) (llvm/trunk 257107)"} +!9 = !DILocalVariable(name: "v1", scope: !10, file: !4, line: 136, type: !5) +!10 = distinct !DILexicalBlock(scope: !11, file: !4, line: 136, column: 5) +!11 = distinct !DISubprogram(name: "SetHistorySize", linkageName: "_ZN6__tsan9FastState14SetHistorySizeEi", scope: !"_ZTSN6__tsan9FastStateE", file: !4, line: 135, isLocal: false, isDefinition: true, scopeLine: 135, flags: DIFlagPrototyped, isOptimized: false) +!12 = !DIExpression() +!13 = !DILocation(line: 136, column: 5, scope: !10)