[llvm] 1572742 - [DebugInfo][Docs] Remove `dbg.addr` from docs
J. Ryan Stinnett via llvm-commits
llvm-commits at lists.llvm.org
Thu Mar 2 01:31:16 PST 2023
Author: J. Ryan Stinnett
Date: 2023-03-02T09:29:42Z
New Revision: 1572742cfa10c12f66acb119190ffdf2db6e941c
URL: https://github.com/llvm/llvm-project/commit/1572742cfa10c12f66acb119190ffdf2db6e941c
DIFF: https://github.com/llvm/llvm-project/commit/1572742cfa10c12f66acb119190ffdf2db6e941c.diff
LOG: [DebugInfo][Docs] Remove `dbg.addr` from docs
Part of `dbg.addr` removal
Discussed in https://discourse.llvm.org/t/what-is-the-status-of-dbg-addr/62898
Differential Revision: https://reviews.llvm.org/D144792
Added:
Modified:
llvm/docs/AssignmentTracking.md
llvm/docs/LangRef.rst
llvm/docs/ReleaseNotes.rst
llvm/docs/SourceLevelDebugging.rst
Removed:
################################################################################
diff --git a/llvm/docs/AssignmentTracking.md b/llvm/docs/AssignmentTracking.md
index ad9f790e7501..5a8bc5844eef 100644
--- a/llvm/docs/AssignmentTracking.md
+++ b/llvm/docs/AssignmentTracking.md
@@ -226,10 +226,10 @@ to tackle:
the storage address is not computed by an instruction (it's an argument
value) and therefore we have nowhere to put the metadata attachment. To solve
this we probably need another marker intrinsic to denote "the variable's
- stack home is X address" - similar to `llvm.dbg.declare` and `llvm.dbg.addr`
- except that it needs to compose with `llvm.dbg.assign` intrinsics such that
- the stack home address is only selected as a location for the variable when
- the `llvm.dbg.assign` intrinsics agree it should be.
+ stack home is X address" - similar to `llvm.dbg.declare` except that it needs
+ to compose with `llvm.dbg.assign` intrinsics such that the stack home address
+ is only selected as a location for the variable when the `llvm.dbg.assign`
+ intrinsics agree it should be.
* Given the above (a special "the stack home is X" intrinsic), and the fact
that we can only track assignments with fixed offsets and sizes, I think we
diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index f420896bf270..7f366d54a9fb 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -6054,10 +6054,10 @@ sense that a debugger might modify its value), whereas *implicit locations*
describe merely the actual *value* of a source variable which might not exist
in registers or in memory (see ``DW_OP_stack_value``).
-A ``llvm.dbg.addr`` or ``llvm.dbg.declare`` intrinsic describes an indirect
-value (the address) of a source variable. The first operand of the intrinsic
-must be an address of some kind. A DIExpression attached to the intrinsic
-refines this address to produce a concrete location for the source variable.
+A ``llvm.dbg.declare`` intrinsic describes an indirect value (the address) of a
+source variable. The first operand of the intrinsic must be an address of some
+kind. A DIExpression attached to the intrinsic refines this address to produce a
+concrete location for the source variable.
A ``llvm.dbg.value`` intrinsic describes the direct value of a source variable.
The first operand of the intrinsic may be a direct or indirect value. A
diff --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst
index aed1df36b490..718f57dba3ee 100644
--- a/llvm/docs/ReleaseNotes.rst
+++ b/llvm/docs/ReleaseNotes.rst
@@ -163,12 +163,19 @@ Changes to the Metadata Info
Changes to the Debug Info
---------------------------------
-* The DWARFv5 feature of attaching `DW_AT_default_value` to defaulted template
+* The DWARFv5 feature of attaching ``DW_AT_default_value`` to defaulted template
parameters will now be available in any non-strict DWARF mode and in a wider
- range of cases than previously. (`D139953 <https://reviews.llvm.org/D139953>`_, `D139988 <https://reviews.llvm.org/D139988>`_)
+ range of cases than previously.
+ (`D139953 <https://reviews.llvm.org/D139953>`_,
+ `D139988 <https://reviews.llvm.org/D139988>`_)
-* The `DW_AT_name` on `DW_AT_typedef`s for alias templates will now omit defaulted
- template parameters. (`D142268 <https://reviews.llvm.org/D142268>`_)
+* The ``DW_AT_name`` on ``DW_AT_typedef``\ s for alias templates will now omit
+ defaulted template parameters. (`D142268 <https://reviews.llvm.org/D142268>`_)
+
+* The experimental ``@llvm.dbg.addr`` intrinsic has been removed (`D144801
+ <https://reviews.llvm.org/D144801>`_). IR inputs with this intrinsic are
+ auto-upgraded to ``@llvm.dbg.value`` with ``DW_OP_deref`` appended to the
+ ``DIExpression`` (`D144793 <https://reviews.llvm.org/D144793>`_).
Changes to the LLVM tools
---------------------------------
diff --git a/llvm/docs/SourceLevelDebugging.rst b/llvm/docs/SourceLevelDebugging.rst
index 07468b1e75f1..be288f6f7f17 100644
--- a/llvm/docs/SourceLevelDebugging.rst
+++ b/llvm/docs/SourceLevelDebugging.rst
@@ -175,62 +175,45 @@ Debugger intrinsic functions
LLVM uses several intrinsic functions (name prefixed with "``llvm.dbg``") to
track source local variables through optimization and code generation.
-``llvm.dbg.addr``
+``llvm.dbg.declare``
^^^^^^^^^^^^^^^^^^^^
.. code-block:: llvm
- void @llvm.dbg.addr(metadata, metadata, metadata)
+ void @llvm.dbg.declare(metadata, metadata, metadata)
This intrinsic provides information about a local element (e.g., variable).
The first argument is metadata holding the address of variable, typically a
static alloca in the function entry block. The second argument is a
`local variable <LangRef.html#dilocalvariable>`_ containing a description of
the variable. The third argument is a `complex expression
-<LangRef.html#diexpression>`_. An `llvm.dbg.addr` intrinsic describes the
+<LangRef.html#diexpression>`_. An `llvm.dbg.declare` intrinsic describes the
*address* of a source variable.
.. code-block:: text
%i.addr = alloca i32, align 4
- call void @llvm.dbg.addr(metadata i32* %i.addr, metadata !1,
- metadata !DIExpression()), !dbg !2
+ call void @llvm.dbg.declare(metadata i32* %i.addr, metadata !1,
+ metadata !DIExpression()), !dbg !2
!1 = !DILocalVariable(name: "i", ...) ; int i
!2 = !DILocation(...)
...
%buffer = alloca [256 x i8], align 8
; The address of i is buffer+64.
- call void @llvm.dbg.addr(metadata [256 x i8]* %buffer, metadata !3,
- metadata !DIExpression(DW_OP_plus, 64)), !dbg !4
+ call void @llvm.dbg.declare(metadata [256 x i8]* %buffer, metadata !3,
+ metadata !DIExpression(DW_OP_plus, 64)), !dbg !4
!3 = !DILocalVariable(name: "i", ...) ; int i
!4 = !DILocation(...)
-A frontend should generate exactly one call to ``llvm.dbg.addr`` at the point
+A frontend should generate exactly one call to ``llvm.dbg.declare`` at the point
of declaration of a source variable. Optimization passes that fully promote the
-variable from memory to SSA values will replace this call with possibly
-multiple calls to `llvm.dbg.value`. Passes that delete stores are effectively
-partial promotion, and they will insert a mix of calls to ``llvm.dbg.value``
-and ``llvm.dbg.addr`` to track the source variable value when it is available.
-After optimization, there may be multiple calls to ``llvm.dbg.addr`` describing
-the program points where the variables lives in memory. All calls for the same
-concrete source variable must agree on the memory location.
-
-
-``llvm.dbg.declare``
-^^^^^^^^^^^^^^^^^^^^
-
-.. code-block:: llvm
-
- void @llvm.dbg.declare(metadata, metadata, metadata)
-
-This intrinsic is identical to `llvm.dbg.addr`, except that there can only be
-one call to `llvm.dbg.declare` for a given concrete `local variable
-<LangRef.html#dilocalvariable>`_. It is not control-dependent, meaning that if
-a call to `llvm.dbg.declare` exists and has a valid location argument, that
-address is considered to be the true home of the variable across its entire
-lifetime. This makes it hard for optimizations to preserve accurate debug info
-in the presence of ``llvm.dbg.declare``, so we are transitioning away from it,
-and we plan to deprecate it in future LLVM releases.
+variable from memory to SSA values will replace this call with possibly multiple
+calls to `llvm.dbg.value`. Passes that delete stores are effectively partial
+promotion, and they will insert a mix of calls to ``llvm.dbg.value`` to track
+the source variable value when it is available. After optimization, there may be
+multiple calls to ``llvm.dbg.declare`` describing the program points where the
+variables lives in memory. All calls for the same concrete source variable must
+agree on the memory location.
``llvm.dbg.value``
@@ -312,9 +295,6 @@ following C fragment, for example:
8. X = Y;
9. }
-.. FIXME: Update the following example to use llvm.dbg.addr once that is the
- default in clang.
-
Compiled to LLVM, this function would be represented like this:
.. code-block:: text
@@ -609,8 +589,8 @@ in IR the location would be assigned ``undef`` by a debug intrinsic, and in MIR
the equivalent location is used.
After MIR locations are assigned to each variable, machine pseudo-instructions
-corresponding to each ``llvm.dbg.value`` and ``llvm.dbg.addr`` intrinsic are
-inserted. There are two forms of this type of instruction.
+corresponding to each ``llvm.dbg.value`` intrinsic are inserted. There are two
+forms of this type of instruction.
The first form, ``DBG_VALUE``, appears thus:
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