Files
clang-p2996/llvm/test/DebugInfo/X86/DW_AT_location-reference.ll
Jeremy Morse 313d2ce999 [DebugInfo] LiveDebugValues should always revisit backedges if it skips them
The "join" method in LiveDebugValues does not attempt to join unseen
predecessor blocks if their out-locations aren't yet initialized, instead
the block should be re-visited later to see if any locations have changed
validity. However, because the set of blocks were all being "process"'d
once before "join" saw them, that logic in "join" was actually ignoring
legitimate out-locations on the first pass through. This meant that some
invalidated locations were not removed from the head of loops, allowing
illegal locations to persist.

Fix this by removing the run of "process" before the main join/process loop
in ExtendRanges. Now the unseen predecessors that "join" skips truly are
uninitialized, and we come back to the block at a later time to re-run
"join", see the @baz function added.

This also fixes another fault where stack/register transfers in the entry
block (or any other before-any-loop-block) had their tranfers initially
ignored, and were then never revisited. The MIR test added tests for this
behaviour.

XFail a test that exposes another bug; a fix for this is coming in D66895.

Differential Revision: https://reviews.llvm.org/D66663

llvm-svn: 370328
2019-08-29 10:53:29 +00:00

119 lines
5.0 KiB
LLVM

; RUN: llc -O1 -filetype=obj -mtriple=x86_64-apple-darwin < %s > %t
; RUN: llvm-dwarfdump -v %t | FileCheck %s
; RUN: llvm-objdump -r %t | FileCheck -check-prefix=DARWIN %s
; RUN: llc -O1 -filetype=obj -mtriple=x86_64-pc-linux-gnu < %s > %t
; RUN: llvm-dwarfdump -v %t | FileCheck %s
; RUN: llvm-objdump -r %t | FileCheck -check-prefix=LINUX %s
; PR9493
; Adapted from the original test case in r127757.
; We use 'llc -O1' to induce variable 'x' to live in different locations.
; We don't actually care where 'x' lives, or what exact optimizations get
; used, as long as 'x' moves around we're fine.
; // The variable 'x' lives in different locations, so it needs an entry in
; // the .debug_loc table section, referenced by DW_AT_location.
; // This ref is not relocatable on Darwin, and is relocatable elsewhere.
; extern int g(int, int);
; extern int a;
;
; void f(void) {
; int x;
; a = g(0, 0);
; x = 1;
; while (x & 1) { x *= a; }
; a = g(x, 0);
; x = 2;
; while (x & 2) { x *= a; }
; a = g(0, x);
; }
; // The 'x' variable and its symbol reference location
; CHECK: .debug_info contents:
; CHECK: DW_TAG_variable
; CHECK-NEXT: DW_AT_location [DW_FORM_sec_offset] (0x00000000
; Check that the location contains only 2 ranges.
; CHECK-NEXT: [0x{{[0-9a-f]*}}, 0x{{[0-9a-f]*}}):
; CHECK-NEXT: [0x{{[0-9a-f]*}}, 0x{{[0-9a-f]*}}): {{.*}})
; CHECK-NEXT: DW_AT_name {{.*}} "x"
; CHECK-NEXT: DW_AT_decl_file
; CHECK-NEXT: DW_AT_decl_line
; CHECK-NEXT: DW_AT_type
; Check that we have no relocations in Darwin's output.
; DARWIN-NOT: X86_64_RELOC{{.*}} __debug_loc
; Check we have a relocation for the debug_loc entry in Linux output.
; LINUX: RELOCATION RECORDS FOR [.debug_info]
; LINUX-NOT: RELOCATION RECORDS
; LINUX: R_X86_64{{.*}} .debug_loc
; ModuleID = 'simple.c'
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-n32"
@a = external global i32
define void @f() nounwind !dbg !0 {
entry:
%call = tail call i32 @g(i32 0, i32 0) nounwind, !dbg !8
store i32 %call, i32* @a, align 4, !dbg !8
tail call void @llvm.dbg.value(metadata i32 1, metadata !5, metadata !DIExpression()), !dbg !13
br label %while.body
while.body: ; preds = %entry, %while.body
%x.017 = phi i32 [ 1, %entry ], [ %mul, %while.body ]
%mul = mul nsw i32 %call, %x.017, !dbg !14
%and = and i32 %mul, 1, !dbg !14
%tobool = icmp eq i32 %and, 0, !dbg !14
br i1 %tobool, label %while.end, label %while.body, !dbg !14
while.end: ; preds = %while.body
tail call void @llvm.dbg.value(metadata i32 %mul, metadata !5, metadata !DIExpression()), !dbg !14
%call4 = tail call i32 @g(i32 %mul, i32 0) nounwind, !dbg !15
store i32 %call4, i32* @a, align 4, !dbg !15
tail call void @llvm.dbg.value(metadata i32 2, metadata !5, metadata !DIExpression()), !dbg !17
br label %while.body9
while.body9: ; preds = %while.end, %while.body9
%x.116 = phi i32 [ 2, %while.end ], [ %mul12, %while.body9 ]
%mul12 = mul nsw i32 %call4, %x.116, !dbg !18
%and7 = and i32 %mul12, 2, !dbg !18
%tobool8 = icmp eq i32 %and7, 0, !dbg !18
br i1 %tobool8, label %while.end13, label %while.body9, !dbg !18
while.end13: ; preds = %while.body9
tail call void @llvm.dbg.value(metadata i32 %mul12, metadata !5, metadata !DIExpression()), !dbg !18
%call15 = tail call i32 @g(i32 0, i32 %mul12) nounwind, !dbg !19
store i32 %call15, i32* @a, align 4, !dbg !19
ret void, !dbg !20
}
declare i32 @g(i32, i32)
declare void @llvm.dbg.value(metadata, metadata, metadata) nounwind readnone
!llvm.dbg.cu = !{!2}
!llvm.module.flags = !{!24}
!0 = distinct !DISubprogram(name: "f", line: 4, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !2, scopeLine: 4, file: !23, scope: !1, type: !3, retainedNodes: !22)
!1 = !DIFile(filename: "simple.c", directory: "/home/rengol01/temp/tests/dwarf/relocation")
!2 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang version 3.0 (trunk)", isOptimized: true, emissionKind: FullDebug, file: !23, enums: !{}, retainedTypes: !{}, imports: null)
!3 = !DISubroutineType(types: !4)
!4 = !{null}
!5 = !DILocalVariable(name: "x", line: 5, scope: !6, file: !1, type: !7)
!6 = distinct !DILexicalBlock(line: 4, column: 14, file: !23, scope: !0)
!7 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!8 = !DILocation(line: 6, column: 3, scope: !6)
!12 = !{i32 1}
!13 = !DILocation(line: 7, column: 3, scope: !6)
!14 = !DILocation(line: 8, column: 3, scope: !6)
!15 = !DILocation(line: 9, column: 3, scope: !6)
!16 = !{i32 2}
!17 = !DILocation(line: 10, column: 3, scope: !6)
!18 = !DILocation(line: 11, column: 3, scope: !6)
!19 = !DILocation(line: 12, column: 3, scope: !6)
!20 = !DILocation(line: 13, column: 1, scope: !6)
!22 = !{!5}
!23 = !DIFile(filename: "simple.c", directory: "/home/rengol01/temp/tests/dwarf/relocation")
!24 = !{i32 1, !"Debug Info Version", i32 3}