diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp index eaf73ee5e68..f69c750f3f9 100644 --- a/lib/Transforms/Scalar/SROA.cpp +++ b/lib/Transforms/Scalar/SROA.cpp @@ -4153,8 +4153,13 @@ bool SROA::splitAlloca(AllocaInst &AI, AllocaSlices &AS) { for (auto &P : AS.partitions()) { if (AllocaInst *NewAI = rewritePartition(AI, AS, P)) { Changed = true; - if (NewAI != &AI) - Pieces.push_back(Piece(NewAI, P.beginOffset(), P.size())); + if (NewAI != &AI) { + uint64_t SizeOfByte = 8; + uint64_t AllocaSize = DL->getTypeSizeInBits(NewAI->getAllocatedType()); + // Don't include any padding. + uint64_t Size = std::min(AllocaSize, P.size() * SizeOfByte); + Pieces.push_back(Piece(NewAI, P.beginOffset() * SizeOfByte, Size)); + } } ++NumPartitions; } @@ -4178,12 +4183,17 @@ bool SROA::splitAlloca(AllocaInst &AI, AllocaSlices &AS) { if (IsSplit || Expr.isBitPiece()) { // If this alloca is already a scalar replacement of a larger aggregate, // Piece.Offset describes the offset inside the scalar. - unsigned Offset = Expr.isBitPiece() ? Expr.getBitPieceOffset() : 0; - assert((Offset == 0 || - Offset+Piece.Offset+Piece.Size*8 <= - Expr.getBitPieceOffset()+Expr.getBitPieceSize()) && - "inner piece is not inside original alloca"); - PieceExpr = DIB.createBitPieceExpression(Offset+Piece.Offset*8, Piece.Size*8); + uint64_t Offset = Expr.isBitPiece() ? Expr.getBitPieceOffset() : 0; + uint64_t Start = Offset + Piece.Offset; + uint64_t Size = Piece.Size; + if (Expr.isBitPiece()) { + uint64_t AbsEnd = Expr.getBitPieceOffset() + Expr.getBitPieceSize(); + if (Start >= AbsEnd) + // No need to describe a SROAed padding. + continue; + Size = std::min(Size, AbsEnd - Start); + } + PieceExpr = DIB.createBitPieceExpression(Start, Size); } // Remove any existing dbg.declare intrinsic describing the same alloca. diff --git a/test/DebugInfo/X86/sroasplit-5.ll b/test/DebugInfo/X86/sroasplit-5.ll new file mode 100644 index 00000000000..9c05e833b1c --- /dev/null +++ b/test/DebugInfo/X86/sroasplit-5.ll @@ -0,0 +1,91 @@ +; RUN: opt %s -sroa -verify -S -o - | FileCheck %s +; From: +; struct prog_src_register { +; unsigned : 4; +; int Index : 12 + 1; +; unsigned : 12; +; unsigned : 4; +; int : 12 + 1 +; } src_reg_for_float() { +; struct prog_src_register a; +; memset(&a, 0, sizeof(a)); +; int local = a.Index; +; return a; +; } +; ModuleID = 'pr22495.c' +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; When SROA is creating new smaller allocas, it may add padding. +; +; There should be no debug info for the padding. +; CHECK-NOT: DW_OP_bit_piece offset=56 +; CHECK: [ DW_TAG_expression ] [DW_OP_bit_piece offset=32, size=24] +; CHECK-NOT: DW_OP_bit_piece offset=56 +; CHECK: [ DW_TAG_expression ] [DW_OP_bit_piece offset=0, size=32] +; CHECK-NOT: DW_OP_bit_piece offset=56 +%struct.prog_src_register = type { i32, i24 } + +; Function Attrs: nounwind +define i64 @src_reg_for_float() #0 { +entry: + %retval = alloca %struct.prog_src_register, align 4 + %a = alloca %struct.prog_src_register, align 4 + %local = alloca i32, align 4 + call void @llvm.dbg.declare(metadata %struct.prog_src_register* %a, metadata !16, metadata !17), !dbg !18 + %0 = bitcast %struct.prog_src_register* %a to i8*, !dbg !19 + call void @llvm.memset.p0i8.i64(i8* %0, i8 0, i64 8, i32 4, i1 false), !dbg !19 + call void @llvm.dbg.declare(metadata i32* %local, metadata !20, metadata !17), !dbg !21 + %1 = bitcast %struct.prog_src_register* %a to i32*, !dbg !21 + %bf.load = load i32* %1, align 4, !dbg !21 + %bf.shl = shl i32 %bf.load, 15, !dbg !21 + %bf.ashr = ashr i32 %bf.shl, 19, !dbg !21 + store i32 %bf.ashr, i32* %local, align 4, !dbg !21 + %2 = bitcast %struct.prog_src_register* %retval to i8*, !dbg !22 + %3 = bitcast %struct.prog_src_register* %a to i8*, !dbg !22 + call void @llvm.memcpy.p0i8.p0i8.i64(i8* %2, i8* %3, i64 8, i32 4, i1 false), !dbg !22 + %4 = bitcast %struct.prog_src_register* %retval to i64*, !dbg !22 + %5 = load i64* %4, align 1, !dbg !22 + ret i64 %5, !dbg !22 +} + +; Function Attrs: nounwind readnone +declare void @llvm.dbg.declare(metadata, metadata, metadata) #1 + +; Function Attrs: nounwind +declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) #2 + +; Function Attrs: nounwind +declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1) #2 + +attributes #0 = { nounwind } +attributes #1 = { nounwind readnone } +attributes #2 = { nounwind } + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!13, !14} +!llvm.ident = !{!15} + +!0 = !{!"0x11\0012\00clang version 3.7.0 \000\00\000\00\001", !1, !2, !2, !3, !2, !2} ; [ DW_TAG_compile_unit ] [/] [DW_LANG_C99] +!1 = !{!"", !""} +!2 = !{} +!3 = !{!4} +!4 = !{!"0x2e\00src_reg_for_float\00src_reg_for_float\00\007\000\001\000\000\000\000\007", !5, !6, !7, null, i64 ()* @src_reg_for_float, null, null, !2} ; [ DW_TAG_subprogram ] [line 7] [def] [src_reg_for_float] +!5 = !{!"pr22495.c", !""} +!6 = !{!"0x29", !5} ; [ DW_TAG_file_type ] [/pr22495.c] +!7 = !{!"0x15\00\000\000\000\000\000\000", null, null, null, !8, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ] +!8 = !{!9} +!9 = !{!"0x13\00prog_src_register\001\0064\0032\000\000\000", !5, null, null, !10, null, null, null} ; [ DW_TAG_structure_type ] [prog_src_register] [line 1, size 64, align 32, offset 0] [def] [from ] +!10 = !{!11} +!11 = !{!"0xd\00Index\003\0013\0032\004\000", !5, !9, !12} ; [ DW_TAG_member ] [Index] [line 3, size 13, align 32, offset 4] [from int] +!12 = !{!"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] +!13 = !{i32 2, !"Dwarf Version", i32 4} +!14 = !{i32 2, !"Debug Info Version", i32 2} +!15 = !{!"clang version 3.7.0 "} +!16 = !{!"0x100\00a\008\000", !4, !6, !9} ; [ DW_TAG_auto_variable ] [a] [line 8] +!17 = !{!"0x102"} ; [ DW_TAG_expression ] +!18 = !MDLocation(line: 8, scope: !4) +!19 = !MDLocation(line: 9, scope: !4) +!20 = !{!"0x100\00local\0010\000", !4, !6, !12} ; [ DW_TAG_auto_variable ] [local] [line 10] +!21 = !MDLocation(line: 10, scope: !4) +!22 = !MDLocation(line: 11, scope: !4)