https://github.com/CarlosAlbertoEnciso updated https://github.com/llvm/llvm-project/pull/66745
>From b24943f63025822a5c5ba90c4a7b47f7123ec4db Mon Sep 17 00:00:00 2001 From: Carlos Alberto Enciso <carlos.alberto.enc...@gmail.com> Date: Mon, 18 Sep 2023 12:29:17 +0100 Subject: [PATCH] [IPSCCP] Variable not visible at Og: https://bugs.llvm.org/show_bug.cgi?id=51559 https://github.com/llvm/llvm-project/issues/50901 IPSCCP pass removes the global variable and does not create a constant expression for the initializer value. --- llvm/lib/Transforms/IPO/SCCP.cpp | 47 +++++++ llvm/test/Transforms/SCCP/pr50901.ll | 184 +++++++++++++++++++++++++++ 2 files changed, 231 insertions(+) create mode 100644 llvm/test/Transforms/SCCP/pr50901.ll diff --git a/llvm/lib/Transforms/IPO/SCCP.cpp b/llvm/lib/Transforms/IPO/SCCP.cpp index 84f5bbf7039416b..e09769e00148143 100644 --- a/llvm/lib/Transforms/IPO/SCCP.cpp +++ b/llvm/lib/Transforms/IPO/SCCP.cpp @@ -22,6 +22,7 @@ #include "llvm/Analysis/ValueTracking.h" #include "llvm/IR/AttributeMask.h" #include "llvm/IR/Constants.h" +#include "llvm/IR/DIBuilder.h" #include "llvm/IR/IntrinsicInst.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/ModRef.h" @@ -371,6 +372,52 @@ static bool runIPSCCP( StoreInst *SI = cast<StoreInst>(GV->user_back()); SI->eraseFromParent(); } + + // Try to create a debug constant expression for the glbal variable + // initializer value. + SmallVector<DIGlobalVariableExpression *, 1> GVEs; + GV->getDebugInfo(GVEs); + if (GVEs.size() == 1) { + DIBuilder DIB(M); + + // Create integer constant expression. + auto createIntExpression = [&DIB](const Constant *CV) -> DIExpression * { + const APInt &API = dyn_cast<ConstantInt>(CV)->getValue(); + std::optional<uint64_t> InitIntOpt; + if (API.isNonNegative()) + InitIntOpt = API.tryZExtValue(); + else if (auto Temp = API.trySExtValue(); Temp.has_value()) + // Transform a signed optional to unsigned optional. + InitIntOpt = (uint64_t)Temp.value(); + return DIB.createConstantValueExpression(InitIntOpt.value()); + }; + + const Constant *CV = GV->getInitializer(); + Type *Ty = GV->getValueType(); + if (Ty->isIntegerTy()) { + GVEs[0]->replaceOperandWith(1, createIntExpression(CV)); + } else if (Ty->isFloatTy() || Ty->isDoubleTy()) { + const APFloat &APF = dyn_cast<ConstantFP>(CV)->getValueAPF(); + DIExpression *NewExpr = DIB.createConstantValueExpression( + APF.bitcastToAPInt().getZExtValue()); + GVEs[0]->replaceOperandWith(1, NewExpr); + } else if (Ty->isPointerTy()) { + if (isa<ConstantPointerNull>(CV)) { + GVEs[0]->replaceOperandWith(1, DIB.createConstantValueExpression(0)); + } else { + if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) { + if (CE->getNumOperands() == 1) { + const Value *V = CE->getOperand(0); + const Constant *CV = dyn_cast<Constant>(V); + if (CV && !isa<GlobalValue>(CV)) + if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) + GVEs[0]->replaceOperandWith(1, createIntExpression(CI)); + } + } + } + } + } + MadeChanges = true; M.eraseGlobalVariable(GV); ++NumGlobalConst; diff --git a/llvm/test/Transforms/SCCP/pr50901.ll b/llvm/test/Transforms/SCCP/pr50901.ll new file mode 100644 index 000000000000000..56961d2e32db41c --- /dev/null +++ b/llvm/test/Transforms/SCCP/pr50901.ll @@ -0,0 +1,184 @@ +; RUN: opt -passes=ipsccp -S -o - < %s | FileCheck %s + +; Global variables g_11, g_22, g_33, g_44, g_55, g_66 and g_77 +; are not visible in the debugger. + +; 1 int g_1 = -4; +; 2 float g_2 = 4.44; +; 3 char g_3 = 'a'; +; 4 unsigned g_4 = 4; +; 5 bool g_5 = true; +; 6 int *g_6 = nullptr; +; 7 float *g_7 = nullptr; +; 8 +; 9 static int g_11 = -5; +; 10 static float g_22 = 5.55; +; 11 static char g_33 = 'b'; +; 12 static unsigned g_44 = 5; +; 13 static bool g_55 = true; +; 14 static int *g_66 = nullptr; +; 15 static float *g_77 = (float *)(55 + 15); +; 16 +; 17 void bar() { +; 18 g_1 = g_11; +; 19 g_2 = g_22; +; 20 g_3 = g_33; +; 21 g_4 = g_44; +; 22 g_5 = g_55; +; 23 g_6 = g_66; +; 24 g_7 = g_77; +; 25 } +; 26 +; 27 int main() { +; 28 { +; 29 bar(); +; 30 } +; 31 } + +; CHECK: ![[G1:[0-9]+]] = !DIGlobalVariableExpression(var: ![[DBG1:[0-9]+]], expr: !DIExpression(DW_OP_constu, 18446744073709551611, DW_OP_stack_value)) +; CHECK-DAG: ![[DBG1]] = distinct !DIGlobalVariable(name: "g_11", {{.*}} +; CHECK: ![[G2:[0-9]+]] = !DIGlobalVariableExpression(var: ![[DBG2:[0-9]+]], expr: !DIExpression(DW_OP_constu, 1085381018, DW_OP_stack_value)) +; CHECK-DAG: ![[DBG2]] = distinct !DIGlobalVariable(name: "g_22", {{.*}} +; CHECK: ![[G3:[0-9]+]] = !DIGlobalVariableExpression(var: ![[DBG3:[0-9]+]], expr: !DIExpression(DW_OP_constu, 98, DW_OP_stack_value)) +; CHECK-DAG: ![[DBG3]] = distinct !DIGlobalVariable(name: "g_33", {{.*}} +; CHECK: ![[G4:[0-9]+]] = !DIGlobalVariableExpression(var: ![[DBG4:[0-9]+]], expr: !DIExpression(DW_OP_constu, 5, DW_OP_stack_value)) +; CHECK-DAG: ![[DBG4]] = distinct !DIGlobalVariable(name: "g_44", {{.*}} +; CHECK: ![[G5:[0-9]+]] = !DIGlobalVariableExpression(var: ![[DBG5:[0-9]+]], expr: !DIExpression(DW_OP_constu, 1, DW_OP_stack_value)) +; CHECK-DAG: ![[DBG5]] = distinct !DIGlobalVariable(name: "g_55", {{.*}} +; CHECK: ![[G6:[0-9]+]] = !DIGlobalVariableExpression(var: ![[DBG6:[0-9]+]], expr: !DIExpression(DW_OP_constu, 0, DW_OP_stack_value)) +; CHECK-DAG: ![[DBG6]] = distinct !DIGlobalVariable(name: "g_66", {{.*}} +; CHECK: ![[G7:[0-9]+]] = !DIGlobalVariableExpression(var: ![[DBG7:[0-9]+]], expr: !DIExpression(DW_OP_constu, 70, DW_OP_stack_value)) +; CHECK-DAG: ![[DBG7]] = distinct !DIGlobalVariable(name: "g_77", {{.*}} + +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-pc-linux-gnu" + +@g_1 = dso_local global i32 -4, align 4, !dbg !0 +@g_2 = dso_local global float 0x4011C28F60000000, align 4, !dbg !8 +@g_3 = dso_local global i8 97, align 1, !dbg !10 +@g_4 = dso_local global i32 4, align 4, !dbg !13 +@g_5 = dso_local global i8 1, align 1, !dbg !16 +@g_6 = dso_local global ptr null, align 8, !dbg !19 +@g_7 = dso_local global ptr null, align 8, !dbg !23 +@_ZL4g_11 = internal global i32 -5, align 4, !dbg !25 +@_ZL4g_22 = internal global float 0x4016333340000000, align 4, !dbg !27 +@_ZL4g_33 = internal global i8 98, align 1, !dbg !29 +@_ZL4g_44 = internal global i32 5, align 4, !dbg !31 +@_ZL4g_55 = internal global i8 1, align 1, !dbg !33 +@_ZL4g_66 = internal global ptr null, align 8, !dbg !35 +@_ZL4g_77 = internal global ptr inttoptr (i64 70 to ptr), align 8, !dbg !37 + +define dso_local void @_Z3barv() !dbg !46 { +entry: + %0 = load i32, ptr @_ZL4g_11, align 4, !dbg !49, !tbaa !50 + store i32 %0, ptr @g_1, align 4, !dbg !54, !tbaa !50 + %1 = load float, ptr @_ZL4g_22, align 4, !dbg !55, !tbaa !56 + store float %1, ptr @g_2, align 4, !dbg !58, !tbaa !56 + %2 = load i8, ptr @_ZL4g_33, align 1, !dbg !59, !tbaa !60 + store i8 %2, ptr @g_3, align 1, !dbg !61, !tbaa !60 + %3 = load i32, ptr @_ZL4g_44, align 4, !dbg !62, !tbaa !50 + store i32 %3, ptr @g_4, align 4, !dbg !63, !tbaa !50 + %4 = load i8, ptr @_ZL4g_55, align 1, !dbg !64, !tbaa !65, !range !67, !noundef !68 + %tobool = trunc i8 %4 to i1, !dbg !64 + %frombool = zext i1 %tobool to i8, !dbg !69 + store i8 %frombool, ptr @g_5, align 1, !dbg !69, !tbaa !65 + %5 = load ptr, ptr @_ZL4g_66, align 8, !dbg !70, !tbaa !71 + store ptr %5, ptr @g_6, align 8, !dbg !73, !tbaa !71 + %6 = load ptr, ptr @_ZL4g_77, align 8, !dbg !74, !tbaa !71 + store ptr %6, ptr @g_7, align 8, !dbg !75, !tbaa !71 + ret void, !dbg !76 +} + +define dso_local noundef i32 @main() !dbg !77 { +entry: + call void @_Z3barv(), !dbg !80 + ret i32 0, !dbg !82 +} + +!llvm.dbg.cu = !{!2} +!llvm.module.flags = !{!39, !40, !41, !42, !43, !44} +!llvm.ident = !{!45} + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "g_1", scope: !2, file: !3, line: 1, type: !22, isLocal: false, isDefinition: true) +!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !3, producer: "clang version 18.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, retainedTypes: !4, globals: !7, splitDebugInlining: false, nameTableKind: None) +!3 = !DIFile(filename: "test.cpp", directory: "") +!4 = !{!5} +!5 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !6, size: 64) +!6 = !DIBasicType(name: "float", size: 32, encoding: DW_ATE_float) +!7 = !{!0, !8, !10, !13, !16, !19, !23, !25, !27, !29, !31, !33, !35, !37} +!8 = !DIGlobalVariableExpression(var: !9, expr: !DIExpression()) +!9 = distinct !DIGlobalVariable(name: "g_2", scope: !2, file: !3, line: 2, type: !6, isLocal: false, isDefinition: true) +!10 = !DIGlobalVariableExpression(var: !11, expr: !DIExpression()) +!11 = distinct !DIGlobalVariable(name: "g_3", scope: !2, file: !3, line: 3, type: !12, isLocal: false, isDefinition: true) +!12 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char) +!13 = !DIGlobalVariableExpression(var: !14, expr: !DIExpression()) +!14 = distinct !DIGlobalVariable(name: "g_4", scope: !2, file: !3, line: 4, type: !15, isLocal: false, isDefinition: true) +!15 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned) +!16 = !DIGlobalVariableExpression(var: !17, expr: !DIExpression()) +!17 = distinct !DIGlobalVariable(name: "g_5", scope: !2, file: !3, line: 5, type: !18, isLocal: false, isDefinition: true) +!18 = !DIBasicType(name: "bool", size: 8, encoding: DW_ATE_boolean) +!19 = !DIGlobalVariableExpression(var: !20, expr: !DIExpression()) +!20 = distinct !DIGlobalVariable(name: "g_6", scope: !2, file: !3, line: 6, type: !21, isLocal: false, isDefinition: true) +!21 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !22, size: 64) +!22 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!23 = !DIGlobalVariableExpression(var: !24, expr: !DIExpression()) +!24 = distinct !DIGlobalVariable(name: "g_7", scope: !2, file: !3, line: 7, type: !5, isLocal: false, isDefinition: true) +!25 = !DIGlobalVariableExpression(var: !26, expr: !DIExpression()) +!26 = distinct !DIGlobalVariable(name: "g_11", linkageName: "_ZL4g_11", scope: !2, file: !3, line: 9, type: !22, isLocal: true, isDefinition: true) +!27 = !DIGlobalVariableExpression(var: !28, expr: !DIExpression()) +!28 = distinct !DIGlobalVariable(name: "g_22", linkageName: "_ZL4g_22", scope: !2, file: !3, line: 10, type: !6, isLocal: true, isDefinition: true) +!29 = !DIGlobalVariableExpression(var: !30, expr: !DIExpression()) +!30 = distinct !DIGlobalVariable(name: "g_33", linkageName: "_ZL4g_33", scope: !2, file: !3, line: 11, type: !12, isLocal: true, isDefinition: true) +!31 = !DIGlobalVariableExpression(var: !32, expr: !DIExpression()) +!32 = distinct !DIGlobalVariable(name: "g_44", linkageName: "_ZL4g_44", scope: !2, file: !3, line: 12, type: !15, isLocal: true, isDefinition: true) +!33 = !DIGlobalVariableExpression(var: !34, expr: !DIExpression()) +!34 = distinct !DIGlobalVariable(name: "g_55", linkageName: "_ZL4g_55", scope: !2, file: !3, line: 13, type: !18, isLocal: true, isDefinition: true) +!35 = !DIGlobalVariableExpression(var: !36, expr: !DIExpression()) +!36 = distinct !DIGlobalVariable(name: "g_66", linkageName: "_ZL4g_66", scope: !2, file: !3, line: 14, type: !21, isLocal: true, isDefinition: true) +!37 = !DIGlobalVariableExpression(var: !38, expr: !DIExpression()) +!38 = distinct !DIGlobalVariable(name: "g_77", linkageName: "_ZL4g_77", scope: !2, file: !3, line: 15, type: !5, isLocal: true, isDefinition: true) +!39 = !{i32 7, !"Dwarf Version", i32 5} +!40 = !{i32 2, !"Debug Info Version", i32 3} +!41 = !{i32 1, !"wchar_size", i32 4} +!42 = !{i32 8, !"PIC Level", i32 2} +!43 = !{i32 7, !"PIE Level", i32 2} +!44 = !{i32 7, !"uwtable", i32 2} +!45 = !{!"clang version 18.0.0"} +!46 = distinct !DISubprogram(name: "bar", linkageName: "_Z3barv", scope: !3, file: !3, line: 17, type: !47, scopeLine: 17, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2) +!47 = !DISubroutineType(types: !48) +!48 = !{null} +!49 = !DILocation(line: 18, column: 9, scope: !46) +!50 = !{!51, !51, i64 0} +!51 = !{!"int", !52, i64 0} +!52 = !{!"omnipotent char", !53, i64 0} +!53 = !{!"Simple C++ TBAA"} +!54 = !DILocation(line: 18, column: 7, scope: !46) +!55 = !DILocation(line: 19, column: 9, scope: !46) +!56 = !{!57, !57, i64 0} +!57 = !{!"float", !52, i64 0} +!58 = !DILocation(line: 19, column: 7, scope: !46) +!59 = !DILocation(line: 20, column: 9, scope: !46) +!60 = !{!52, !52, i64 0} +!61 = !DILocation(line: 20, column: 7, scope: !46) +!62 = !DILocation(line: 21, column: 9, scope: !46) +!63 = !DILocation(line: 21, column: 7, scope: !46) +!64 = !DILocation(line: 22, column: 9, scope: !46) +!65 = !{!66, !66, i64 0} +!66 = !{!"bool", !52, i64 0} +!67 = !{i8 0, i8 2} +!68 = !{} +!69 = !DILocation(line: 22, column: 7, scope: !46) +!70 = !DILocation(line: 23, column: 9, scope: !46) +!71 = !{!72, !72, i64 0} +!72 = !{!"any pointer", !52, i64 0} +!73 = !DILocation(line: 23, column: 7, scope: !46) +!74 = !DILocation(line: 24, column: 9, scope: !46) +!75 = !DILocation(line: 24, column: 7, scope: !46) +!76 = !DILocation(line: 25, column: 1, scope: !46) +!77 = distinct !DISubprogram(name: "main", scope: !3, file: !3, line: 27, type: !78, scopeLine: 27, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2) +!78 = !DISubroutineType(types: !79) +!79 = !{!22} +!80 = !DILocation(line: 29, column: 5, scope: !81) +!81 = distinct !DILexicalBlock(scope: !77, file: !3, line: 28, column: 3) +!82 = !DILocation(line: 31, column: 1, scope: !77) _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
