From ab699d78a26f147b56537326ecadc072f8f5a03b Mon Sep 17 00:00:00 2001 From: Alok Kumar Sharma Date: Fri, 15 May 2020 10:58:29 +0530 Subject: [PATCH] [DebugInfo] llvm rejects DWARF operator DW_OP_push_object_address llvm rejects DWARF operator DW_OP_push_object_address.This DWARF operator is needed for Flang to support allocatable array. Summary: Currently llvm rejects DWARF operator DW_OP_push_object_address. below error is produced when llvm finds this operator. [..] invalid expression !DIExpression(151) warning: ignoring invalid debug info in pushobj.ll [..] There are some parts missing in support of this operator, need to be completed. Testing -added a unit testcase -check-debuginfo -check-llvm Reviewed By: aprantl Differential Revision: https://reviews.llvm.org/D79306 --- llvm/docs/LangRef.rst | 3 + .../CodeGen/AsmPrinter/DwarfExpression.cpp | 1 + llvm/lib/IR/DebugInfoMetadata.cpp | 1 + .../DebugInfo/dwarfdump-pushobjectaddress.ll | 59 +++++++++++++++++++ 4 files changed, 64 insertions(+) create mode 100644 llvm/test/DebugInfo/dwarfdump-pushobjectaddress.ll diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst index 5845c62a291d..8b5bc8f3a95f 100644 --- a/llvm/docs/LangRef.rst +++ b/llvm/docs/LangRef.rst @@ -5102,6 +5102,9 @@ The current supported opcode vocabulary is limited: signed offset of the specified register. The opcode is only generated by the ``AsmPrinter`` pass to describe call site parameter value which requires an expression over two registers. +- ``DW_OP_push_object_address`` pushes the address of the object which can then + serve as a descriptor in subsequent calculation. This opcode can be used to + calculate bounds of fortran allocatable array which has array descriptors. DWARF specifies three kinds of simple location descriptions: Register, memory, and implicit location descriptions. Note that a location description is diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp index a65d2d74a8c7..69bc06cb9467 100644 --- a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp @@ -451,6 +451,7 @@ void DwarfExpression::addExpression(DIExpressionCursor &&ExprCursor, case dwarf::DW_OP_lit0: case dwarf::DW_OP_not: case dwarf::DW_OP_dup: + case dwarf::DW_OP_push_object_address: emitOp(OpNum); break; case dwarf::DW_OP_deref: diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp index c176d27a52ac..83e0958e21f2 100644 --- a/llvm/lib/IR/DebugInfoMetadata.cpp +++ b/llvm/lib/IR/DebugInfoMetadata.cpp @@ -947,6 +947,7 @@ bool DIExpression::isValid() const { case dwarf::DW_OP_dup: case dwarf::DW_OP_regx: case dwarf::DW_OP_bregx: + case dwarf::DW_OP_push_object_address: break; } } diff --git a/llvm/test/DebugInfo/dwarfdump-pushobjectaddress.ll b/llvm/test/DebugInfo/dwarfdump-pushobjectaddress.ll new file mode 100644 index 000000000000..012eab6d8465 --- /dev/null +++ b/llvm/test/DebugInfo/dwarfdump-pushobjectaddress.ll @@ -0,0 +1,59 @@ +;; This test checks whether DWARF operator DW_OP_push_object_address +;; is accepted and processed. + +; RUN: %llc -mtriple=x86_64-unknown-linux-gnu %s -filetype=obj -o - | llvm-dwarfdump - | FileCheck %s + +;; Test whether DW_OP_push_object_address is accepted. + +; CHECK-LABEL: DW_TAG_variable +; CHECK: DW_AT_location +; CHECK-SAME: DW_OP_push_object_address + +;; Below is the original test case this IR is generated from +;;--------------------------- +;;int main() { +;;int var; +;;return var; +;;} +;;--------------------------- +;; step 1: generate IR using -g -O0 -S -emit-llvm +;; step 2: insert DW_OP_push_object_address in dbg.declare instruction +;; This is meaningless test case focused to test DW_OP_push_object_address. + +; ModuleID = 'dwarfdump-pushobjectaddress.c' +source_filename = "dwarfdump-pushobjectaddress.c" +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" + +; Function Attrs: noinline nounwind optnone uwtable +define dso_local i32 @main() !dbg !7 { +entry: + %retval = alloca i32, align 4 + %var = alloca i32, align 4 + store i32 0, i32* %retval, align 4 + call void @llvm.dbg.declare(metadata i32* %var, metadata !11, metadata !DIExpression(DW_OP_push_object_address)), !dbg !12 + %0 = load i32, i32* %var, align 4, !dbg !13 + ret i32 %0, !dbg !14 +} + +; Function Attrs: nounwind readnone speculatable willreturn +declare void @llvm.dbg.declare(metadata, metadata, metadata) + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!3, !4, !5} +!llvm.ident = !{!6} + +!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 11.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, nameTableKind: None) +!1 = !DIFile(filename: "dwarfdump-pushobjectaddress.c", directory: "/dir") +!2 = !{} +!3 = !{i32 7, !"Dwarf Version", i32 4} +!4 = !{i32 2, !"Debug Info Version", i32 3} +!5 = !{i32 1, !"wchar_size", i32 4} +!6 = !{!"clang version 11.0.0"} +!7 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 1, type: !8, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2) +!8 = !DISubroutineType(types: !9) +!9 = !{!10} +!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!11 = !DILocalVariable(name: "var", scope: !7, file: !1, line: 2, type: !10) +!12 = !DILocation(line: 2, column: 5, scope: !7) +!13 = !DILocation(line: 3, column: 8, scope: !7) +!14 = !DILocation(line: 3, column: 1, scope: !7)