Fix impGetNodeAddr flag handling for volatile, unaligned, and initclass accesses #122381

Copilot · 2025-12-10T11:27:38Z

impGetNodeAddr returns GTF_IND_COPYABLE_FLAGS (volatile, unaligned, nonfaulting, initclass) from the original access, but five call sites were ignoring these flags, potentially leading to incorrect semantics for volatile/unaligned/initclass operations.

Changes:

Added allowConfiguredDerefs parameter to impGetNodeAddr: When false, indirections with volatile, unaligned, or initclass flags fall through to temp creation instead of returning the address directly. Defaults to true for backward compatibility.
Return buffers (3 sites): Set allowConfiguredDerefs = false when obtaining addresses for return buffer arguments passed to helpers. VM helpers cannot handle addresses with volatile, unaligned, or initclass flags.

Struct field access on instance: Combine flags from impGetNodeAddr with prefix flags when creating the field indirection:

GenTreeFlags objAddrFlags = GTF_EMPTY;
obj = impGetNodeAddr(obj, CHECK_SPILL_ALL, &amp;objAddrFlags);
indirFlags |= objAddrFlags;  // Combine with prefix flags

Box-isinst optimization: Transfer flags to the hasValue field indirection:

objToBox = impGetNodeAddr(objToBox, CHECK_SPILL_ALL, &amp;indirFlags);
impPushOnStack(gtNewIndir(TYP_UBYTE, objToBox, indirFlags), ...);

Fixed recursive call: Preserve allowConfiguredDerefs in GT_COMMA case to maintain semantics through comma expressions.

All five TODO-Bug?: verify if flags matter here comments resolved.

Original prompt

This section details on the original issue you should resolve

<issue_title>Review usages of impGetNodeAddr with ignored flags</issue_title>
<issue_description>#85562 made impGetNodeAddr return flags the original access would use. Places that use the API but ignore the returned flags have been marked with // TODO-Bug?: verify if flags matter here.
All such cases should be reviewed and either documented to be fine or fixed to not ignore the flags.
cc @SingleAccretion </issue_description>

<agent_instructions>For uses that end up indirecting the address, simply transfer the flags on to that indirection.
For uses that do not indirect (e.g. passing the address to a VM helper), add a new argument to impGetNodeAddr about whether volatile and unaligned addresses should be allowed, and if not, fall through to the case that copies to a local.</agent_instructions>

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Issue Details

#85562 made impGetNodeAddr return flags the original access would use. Places that use the API but ignore the returned flags have been marked with // TODO-Bug?: verify if flags matter here.
All such cases should be reviewed and either documented to be fine or fixed to not ignore the flags.
cc @SingleAccretion

Author: MichalPetryka

Assignees: -

Labels:
area-CodeGen-coreclr

Milestone: -

Fixes Review usages of impGetNodeAddr with ignored flags #89372

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Co-authored-by: jakobbotsch <7887810+jakobbotsch@users.noreply.github.com>

src/coreclr/jit/importer.cpp

Co-authored-by: jakobbotsch <7887810+jakobbotsch@users.noreply.github.com>

…IND_INITCLASS Co-authored-by: jakobbotsch <7887810+jakobbotsch@users.noreply.github.com>

src/coreclr/jit/importer.cpp

Copilot

Pull request overview

This PR fixes a bug where impGetNodeAddr was returning flags (volatile, unaligned, nonfaulting, initclass) from the original access, but five call sites were ignoring these flags, potentially leading to incorrect semantics.

Key Changes

Added allowedMustPreserveIndirFlags parameter to impGetNodeAddr to control which flags are acceptable without creating a temp
Updated all call sites to pass appropriate flag masks and use the returned flags where needed
Introduced GTF_IND_MUST_PRESERVE_FLAGS constant to represent flags that must be preserved (volatile, unaligned, initclass)

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/coreclr/jit/gentree.h	Introduces GTF_IND_MUST_PRESERVE_FLAGS constant and updates GTF_IND_COPYABLE_FLAGS to use it
src/coreclr/jit/compiler.h	Updates impGetNodeAddr signature to include allowedMustPreserveIndirFlags parameter
src/coreclr/jit/importer.cpp	Implements new parameter logic in impGetNodeAddr, updates all call sites to pass appropriate flags and use returned flags for indirections
src/coreclr/jit/importercalls.cpp	Updates SRCSUnsafeIntrinsic call site to use the new parameter

src/coreclr/jit/importer.cpp

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

jakobbotsch · 2026-01-09T16:57:20Z

PTAL @dotnet/jit-contrib

No diffs. Removes a number of TODOs.

MihaZupan · 2026-01-13T14:44:42Z

Looks like this broke builds on main since #122167 was merged in between

  FAILED: jit/static/CMakeFiles/clrjit_static.dir/__/importer.cpp.obj
  C:\PROGRA~1\MICROS~3\18\Insiders\VC\Tools\MSVC\1450~1.357\bin\Hostx64\x64\cl.exe  /nologo /TP -DBUILDENV_CHECKED=1 -DDEBUG -DDEBUGGING_SUPPORTED -DFEATURE_BASICFREEZE -DFEATURE_CODE_VERSIONING -DFEATURE_COLLECTIBLE_TYPES -DFEATURE_COMINTEROP -DFEATURE_COMINTEROP_APARTMENT_SUPPORT -DFEATURE_COMINTEROP_UNMANAGED_ACTIVATION -DFEATURE_COMWRAPPERS -DFEATURE_CORECLR -DFEATURE_CORECLR_FLUSH_INSTRUCTION_CACHE_TO_PROTECT_STUB_READS -DFEATURE_DATABREAKPOINT -DFEATURE_DEFAULT_INTERFACES -DFEATURE_EVENT_TRACE -DFEATURE_HIJACK -DFEATURE_HW_INTRINSICS -DFEATURE_IJW -DFEATURE_INTEROP_DEBUGGING -DFEATURE_INTERPRETER -DFEATURE_ISYM_READER -DFEATURE_JAVAMARSHAL -DFEATURE_JIT -DFEATURE_MANUALLY_MANAGED_CARD_BUNDLES -DFEATURE_MASKED_HW_INTRINSICS -DFEATURE_METADATA_UPDATER -DFEATURE_MULTICOREJIT -DFEATURE_PERFTRACING -DFEATURE_PGO -DFEATURE_PROFAPI_ATTACH_DETACH -DFEATURE_READYTORUN -DFEATURE_REJIT -DFEATURE_REMAP_FUNCTION -DFEATURE_SIMD -DFEATURE_SPECIAL_USER_MODE_APC -DFEATURE_STANDALONE_GC -DFEATURE_SVR_GC -DFEATURE_SYMDIFF -DFEATURE_TIERED_COMPILATION -DFEATURE_TYPEEQUIVALENCE -DFEATURE_USE_ASM_GC_WRITE_BARRIERS -DFEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP -DHOST_64BIT -DHOST_AMD64 -DHOST_WINDOWS -DJIT_BUILD -DNOMINMAX -DOUT_OF_PROCESS_SETTHREADCONTEXT -DPROFILING_SUPPORTED -DTARGET_64BIT -DTARGET_AMD64 -DTARGET_WINDOWS -DUNICODE -DUNIX_AMD64_ABI_ITF -DURTBLDENV_FRIENDLY=Checked -DWIN32 -DWIN32_LEAN_AND_MEAN -DWINVER=0x0602 -D_CRT_SECURE_NO_WARNINGS -D_DBG -D_DEBUG -D_FILE_OFFSET_BITS=64 -D_SECURE_SCL=0 -D_TIME_BITS=64 -D_UNICODE -D_WIN32 -D_WIN32_WINNT=0x0602 -IC:\MihaZupan\runtime-debug\artifacts\obj\coreclr\windows.x64.Checked\jit\static -IC:\MihaZupan\runtime-debug\src\coreclr\jit\static -IC:\MihaZupan\runtime-debug\src\native -IC:\MihaZupan\runtime-debug\src\native\inc -IC:\MihaZupan\runtime-debug\src\coreclr\pal\prebuilt\inc -IC:\MihaZupan\runtime-debug\artifacts\obj -IC:\MihaZupan\runtime-debug\src\coreclr\inc -IC:\MihaZupan\runtime-debug\src\coreclr\debug\inc -IC:\MihaZupan\runtime-debug\src\coreclr\debug\inc\amd64 -IC:\MihaZupan\runtime-debug\src\coreclr\debug\inc\dump -IC:\MihaZupan\runtime-debug\src\coreclr\md\inc -IC:\MihaZupan\runtime-debug\artifacts\obj\coreclr\windows.x64.Checked\inc -IC:\MihaZupan\runtime-debug\src\coreclr\hosts\inc -IC:\MihaZupan\runtime-debug\src\coreclr\interpreter\inc -IC:\MihaZupan\runtime-debug\src\coreclr\minipal -IC:\MihaZupan\runtime-debug\artifacts\obj\coreclr\windows.x64.Checked\inc\etw -IC:\MihaZupan\runtime-debug\src\coreclr\jit\.\jitstd -IC:\MihaZupan\runtime-debug\src\coreclr\jit\..\inc -IC:\MihaZupan\runtime-debug\src\coreclr\jit /DWIN32 /D_WINDOWS  /GR- -std:c++17 -MTd /O2 /EHa /nologo /W4 /WX /sdl /Oi /Oy- /Gm- /Zp8 /Gy /fp:precise /FC /MP /Zm200 /Zc:strictStrings /Zc:wchar_t /Zc:inline /Zc:forScope /wd4065 /wd4100 /wd4127 /wd4131 /wd4189 /wd4200 /wd4201 /wd4206 /wd4239 /wd4245 /wd4291 /wd4310 /wd4324 /wd4366 /wd4456 /wd4457 /wd4458 /wd4459 /wd4463 /wd4505 /wd4702 /wd4706 /wd4733 /wd4815 /wd4838 /wd4918 /wd4960 /wd4961 /wd5105 /wd5205 /we4007 /we4013 /we4102 /we4551 /we4640 /we4806 /we4018 /we4055 /we4242 /we4244 /we4267 /we4302 /we4509 /we4510 /we4610 /we4611 /we4701 /w34092 /w34121 /w34125 /w34130 /w34132 /w34212 /w34530 /w35038 /w44177 /Zi /ZH:SHA_256 /source-charset:utf-8 /guard:cf /guard:ehcont /Zl /permissive- /YuC:/MihaZupan/runtime-debug/artifacts/obj/coreclr/windows.x64.Checked/jit/static/CMakeFiles/clrjit_static.dir/cmake_pch.hxx /FpC:/MihaZupan/runtime-debug/artifacts/obj/coreclr/windows.x64.Checked/jit/static/CMakeFiles/clrjit_static.dir/./cmake_pch.cxx.pch /FIC:/MihaZupan/runtime-debug/artifacts/obj/coreclr/windows.x64.Checked/jit/static/CMakeFiles/clrjit_static.dir/cmake_pch.hxx /showIncludes /Fojit\static\CMakeFiles\clrjit_static.dir\__\importer.cpp.obj /Fdjit\static\CMakeFiles\clrjit_static.dir\ /FS -c C:\MihaZupan\runtime-debug\src\coreclr\jit\importer.cpp
  C:\MihaZupan\runtime-debug\src\coreclr\jit\importer.cpp(3401): error C2660: 'Compiler::impGetNodeAddr': function does not take 3 arguments
  C:\MihaZupan\runtime-debug\src\coreclr\jit\importer.cpp(1114): note: see declaration of 'Compiler::impGetNodeAddr'
  C:\MihaZupan\runtime-debug\src\coreclr\jit\importer.cpp(3401): note: while trying to match the argument list '(GenTree *, const unsigned int, GenTreeFlags *)'

jakobbotsch · 2026-01-13T15:01:51Z

#123128 should fix it

Initial plan

741dbd2

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jakobbotsch added area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI and removed needs-area-label An area label is needed to ensure this gets routed to the appropriate area owners labels Dec 10, 2025

Fix impGetNodeAddr flag handling in all 5 locations

98548f2

Co-authored-by: jakobbotsch <7887810+jakobbotsch@users.noreply.github.com>

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Address code review feedback: remove extra blank line

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Fix recursive call and optimize flag checking

270cf27

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Copilot AI changed the title ~~[WIP] Review usages of impGetNodeAddr with ignored flags~~ Fix impGetNodeAddr flag handling for volatile and unaligned accesses Dec 10, 2025

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Rename allowVolatileUnaligned to allowConfiguredDerefs and check GTF_…

7c2aedd

…IND_INITCLASS Co-authored-by: jakobbotsch <7887810+jakobbotsch@users.noreply.github.com>

Copilot AI changed the title ~~Fix impGetNodeAddr flag handling for volatile and unaligned accesses~~ Fix impGetNodeAddr flag handling for volatile, unaligned, and initclass accesses Dec 10, 2025

Copilot finished work on behalf of jakobbotsch December 10, 2025 12:43

Fix bugs, slightly refactor

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build-analysis bot mentioned this pull request Dec 11, 2025

"Over release of MOW - COM" assert in COM wrappers #122447

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JIT: Fix build after two conflicting changes #123128

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[main] Source code updates from dotnet/runtime dotnet/dotnet#4196

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Fix impGetNodeAddr flag handling for volatile, unaligned, and initclass accesses #122381

Fix impGetNodeAddr flag handling for volatile, unaligned, and initclass accesses #122381

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Author:	MichalPetryka
Assignees:	-
Labels:	`area-CodeGen-coreclr`
Milestone:	-

Fix impGetNodeAddr flag handling for volatile, unaligned, and initclass accesses #122381

Fix impGetNodeAddr flag handling for volatile, unaligned, and initclass accesses #122381

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