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[docs] SourceLevelDebugging: fix metadata references (#101187)

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The metadata was off-by-one in a couple of places, making the
explanatory text incorrect.
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Michael Buch 2024-07-30 15:24:07 +01:00 committed by GitHub
parent dcb4399f07
commit 6b08e4d3ac
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1 changed files with 21 additions and 21 deletions
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42
llvm/docs/SourceLevelDebugging.rst
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@ -389,12 +389,12 @@ Compiled to LLVM, this function would be represented like this:
%X = alloca i32, align 4
%Y = alloca i32, align 4
%Z = alloca i32, align 4
#dbg_declare(ptr %X, !11, !DIExpression(), !14)
store i32 21, i32* %X, align 4, !dbg !14
#dbg_declare(ptr %Y, !15, !DIExpression(), !16)
store i32 22, i32* %Y, align 4, !dbg !16
#dbg_declare(ptr %Z, !17, !DIExpression(), !19)
store i32 23, i32* %Z, align 4, !dbg !19
#dbg_declare(ptr %X, !11, !DIExpression(), !13)
store i32 21, i32* %X, align 4, !dbg !13
#dbg_declare(ptr %Y, !14, !DIExpression(), !15)
store i32 22, i32* %Y, align 4, !dbg !15
#dbg_declare(ptr %Z, !16, !DIExpression(), !18)
store i32 23, i32* %Z, align 4, !dbg !18
%0 = load i32, i32* %X, align 4, !dbg !20
store i32 %0, i32* %Z, align 4, !dbg !21
%1 = load i32, i32* %Y, align 4, !dbg !22
@ -427,9 +427,9 @@ Compiled to LLVM, this function would be represented like this:
!15 = !DILocation(line: 3, column: 9, scope: !4)
!16 = !DILocalVariable(name: "Z", scope: !18, file: !1, line: 5, type: !12)
!17 = distinct !DILexicalBlock(scope: !4, file: !1, line: 4, column: 5)
!18 = !DILocation(line: 5, column: 11, scope: !18)
!29 = !DILocation(line: 6, column: 11, scope: !18)
!20 = !DILocation(line: 6, column: 9, scope: !18)
!18 = !DILocation(line: 5, column: 11, scope: !17)
!29 = !DILocation(line: 6, column: 11, scope: !17)
!20 = !DILocation(line: 6, column: 9, scope: !17)
!21 = !DILocation(line: 8, column: 9, scope: !4)
!22 = !DILocation(line: 8, column: 7, scope: !4)
!23 = !DILocation(line: 9, column: 3, scope: !4)
@ -443,21 +443,21 @@ variable definitions, and the code used to implement the function.
.. code-block:: llvm
#dbg_declare(ptr %X, !11, !DIExpression(), !14)
; [debug line = 2:7] [debug variable = X]
#dbg_declare(ptr %X, !11, !DIExpression(), !13)
; [debug line = 2:9] [debug variable = X]
The first record ``#dbg_declare`` encodes debugging information for the
variable ``X``. The location ``!14`` at the end of the record provides
variable ``X``. The location ``!13`` at the end of the record provides
scope information for the variable ``X``.
.. code-block:: text
!14 = !DILocation(line: 2, column: 9, scope: !4)
!13 = !DILocation(line: 2, column: 9, scope: !4)
!4 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 1, type: !5,
isLocal: false, isDefinition: true, scopeLine: 1,
isOptimized: false, retainedNodes: !2)
Here ``!14`` is metadata providing `location information
Here ``!13`` is metadata providing `location information
<LangRef.html#dilocation>`_. In this example, scope is encoded by ``!4``, a
`subprogram descriptor <LangRef.html#disubprogram>`_. This way the location
information parameter to the records indicates that the variable ``X`` is
@ -467,20 +467,20 @@ Now lets take another example.
.. code-block:: llvm
#dbg_declare(ptr %Z, !17, !DIExpression(), !19)
; [debug line = 5:9] [debug variable = Z]
#dbg_declare(ptr %Z, !16, !DIExpression(), !18)
; [debug line = 5:11] [debug variable = Z]
The third record ``#dbg_declare`` encodes debugging information for
variable ``Z``. The metadata ``!19`` at the end of the record provides
variable ``Z``. The metadata ``!18`` at the end of the record provides
scope information for the variable ``Z``.
.. code-block:: text
!18 = distinct !DILexicalBlock(scope: !4, file: !1, line: 4, column: 5)
!19 = !DILocation(line: 5, column: 11, scope: !18)
!17 = distinct !DILexicalBlock(scope: !4, file: !1, line: 4, column: 5)
!18 = !DILocation(line: 5, column: 11, scope: !17)
Here ``!19`` indicates that ``Z`` is declared at line number 5 and column
number 11 inside of lexical scope ``!18``. The lexical scope itself resides
Here ``!18`` indicates that ``Z`` is declared at line number 5 and column
number 11 inside of lexical scope ``!17``. The lexical scope itself resides
inside of subprogram ``!4`` described above.
The scope information attached with each instruction provides a straightforward