From e0652258ac6178df9d3124df17b416b1e6ac7654 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 9 Apr 2026 02:17:12 +0000
Subject: [PATCH 1/2] Move Thread::m_pInterpThreadContext near top of Thread
 class after m_thAllocContextObj

This makes the offset more stable for asm code. The field is no longer at the
end of the class (offsets were 0x290-0xaf8 depending on config), and is now
at a stable offset of 0x30 (64-bit) or 0x1c (32-bit) near the top of the class.

Update OFFSETOF__Thread__m_pInterpThreadContext in all asmconstants.h files
(amd64, arm64, arm, loongarch64, riscv64) to the new stable values. The
conditional compilation guards for _DEBUG and TARGET_UNIX are removed since
the value is now the same in all configurations for each architecture.

Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/21a58369-8e3e-4715-98ba-f11a627ecdfe

Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>
---
 src/coreclr/vm/amd64/asmconstants.h       | 14 +-------------
 src/coreclr/vm/arm/asmconstants.h         |  6 +-----
 src/coreclr/vm/arm64/asmconstants.h       | 10 +---------
 src/coreclr/vm/loongarch64/asmconstants.h |  2 +-
 src/coreclr/vm/riscv64/asmconstants.h     |  2 +-
 src/coreclr/vm/threads.h                  |  5 ++++-
 6 files changed, 9 insertions(+), 30 deletions(-)

diff --git a/src/coreclr/vm/amd64/asmconstants.h b/src/coreclr/vm/amd64/asmconstants.h
index 09aa3fc8d29705..128faf9429ad84 100644
--- a/src/coreclr/vm/amd64/asmconstants.h
+++ b/src/coreclr/vm/amd64/asmconstants.h
@@ -557,19 +557,7 @@ ASMCONSTANTS_C_ASSERT(OFFSETOF__ThreadLocalInfo__m_pThread == offsetof(ThreadLoc
 #endif
 ASMCONSTANTS_C_ASSERT(OFFSETOF__InterpMethod__pCallStub == offsetof(InterpMethod, pCallStub))
 
-#ifdef TARGET_UNIX
-#ifdef _DEBUG
-#define OFFSETOF__Thread__m_pInterpThreadContext 0xaf8
-#else // _DEBUG
-#define OFFSETOF__Thread__m_pInterpThreadContext 0x290
-#endif // _DEBUG
-#else // TARGET_UNIX
-#ifdef _DEBUG
-#define OFFSETOF__Thread__m_pInterpThreadContext 0xb50
-#else // _DEBUG
-#define OFFSETOF__Thread__m_pInterpThreadContext 0x2d8
-#endif // _DEBUG
-#endif // TARGET_UNIX
+#define OFFSETOF__Thread__m_pInterpThreadContext 0x30
 ASMCONSTANTS_C_ASSERT(OFFSETOF__Thread__m_pInterpThreadContext == offsetof(Thread, m_pInterpThreadContext))
 
 #define OFFSETOF__InterpThreadContext__pStackPointer 0x10
diff --git a/src/coreclr/vm/arm/asmconstants.h b/src/coreclr/vm/arm/asmconstants.h
index fd810c0ec5ec86..79c27095656a39 100644
--- a/src/coreclr/vm/arm/asmconstants.h
+++ b/src/coreclr/vm/arm/asmconstants.h
@@ -211,11 +211,7 @@ ASMCONSTANTS_C_ASSERT(OFFSETOF__ThreadLocalInfo__m_pThread == offsetof(ThreadLoc
 #endif
 ASMCONSTANTS_C_ASSERT(OFFSETOF__InterpMethod__pCallStub == offsetof(InterpMethod, pCallStub))
 
-#ifdef TARGET_UNIX
-#define OFFSETOF__Thread__m_pInterpThreadContext 0x630
-#else // TARGET_UNIX
-#define OFFSETOF__Thread__m_pInterpThreadContext 0x0
-#endif // TARGET_UNIX
+#define OFFSETOF__Thread__m_pInterpThreadContext 0x1c
 ASMCONSTANTS_C_ASSERT(OFFSETOF__Thread__m_pInterpThreadContext == offsetof(Thread, m_pInterpThreadContext))
 
 #define OFFSETOF__InterpThreadContext__pStackPointer 0x8
diff --git a/src/coreclr/vm/arm64/asmconstants.h b/src/coreclr/vm/arm64/asmconstants.h
index 1fda62d215f7f4..a79697e3ad1927 100644
--- a/src/coreclr/vm/arm64/asmconstants.h
+++ b/src/coreclr/vm/arm64/asmconstants.h
@@ -292,15 +292,7 @@ ASMCONSTANTS_C_ASSERT(OFFSETOF__ThreadLocalInfo__m_pThread == offsetof(ThreadLoc
 #endif
 ASMCONSTANTS_C_ASSERT(OFFSETOF__InterpMethod__pCallStub == offsetof(InterpMethod, pCallStub))
 
-#ifdef TARGET_UNIX
-#ifdef _DEBUG
-#define OFFSETOF__Thread__m_pInterpThreadContext 0xb20
-#else // _DEBUG
-#define OFFSETOF__Thread__m_pInterpThreadContext 0x2b8
-#endif // _DEBUG
-#else // TARGET_UNIX
-#define OFFSETOF__Thread__m_pInterpThreadContext 0xb48
-#endif // TARGET_UNIX
+#define OFFSETOF__Thread__m_pInterpThreadContext 0x30
 ASMCONSTANTS_C_ASSERT(OFFSETOF__Thread__m_pInterpThreadContext == offsetof(Thread, m_pInterpThreadContext))
 
 #define OFFSETOF__InterpThreadContext__pStackPointer 0x10
diff --git a/src/coreclr/vm/loongarch64/asmconstants.h b/src/coreclr/vm/loongarch64/asmconstants.h
index 3ddc93bf34c396..d675d3180638aa 100644
--- a/src/coreclr/vm/loongarch64/asmconstants.h
+++ b/src/coreclr/vm/loongarch64/asmconstants.h
@@ -218,7 +218,7 @@ ASMCONSTANTS_C_ASSERT(StubPrecodeData__SecretParam        == offsetof(StubPrecod
 #define OFFSETOF__InterpMethod__pCallStub 0x20
 ASMCONSTANTS_C_ASSERT(OFFSETOF__InterpMethod__pCallStub == offsetof(InterpMethod, pCallStub))
 
-#define OFFSETOF__Thread__m_pInterpThreadContext 0xB20
+#define OFFSETOF__Thread__m_pInterpThreadContext 0x30
 ASMCONSTANTS_C_ASSERT(OFFSETOF__Thread__m_pInterpThreadContext == offsetof(Thread, m_pInterpThreadContext))
 
 #define OFFSETOF__InterpThreadContext__pStackPointer 0x10
diff --git a/src/coreclr/vm/riscv64/asmconstants.h b/src/coreclr/vm/riscv64/asmconstants.h
index bc8f8a02444529..de493c425bf66e 100644
--- a/src/coreclr/vm/riscv64/asmconstants.h
+++ b/src/coreclr/vm/riscv64/asmconstants.h
@@ -231,7 +231,7 @@ ASMCONSTANTS_C_ASSERT(OFFSETOF__ThreadLocalInfo__m_pThread == offsetof(ThreadLoc
 #endif
 ASMCONSTANTS_C_ASSERT(OFFSETOF__InterpMethod__pCallStub == offsetof(InterpMethod, pCallStub))
 
-#define OFFSETOF__Thread__m_pInterpThreadContext 0xB20
+#define OFFSETOF__Thread__m_pInterpThreadContext 0x30
 ASMCONSTANTS_C_ASSERT(OFFSETOF__Thread__m_pInterpThreadContext == offsetof(Thread, m_pInterpThreadContext))
 
 #define OFFSETOF__InterpThreadContext__pStackPointer 0x10
diff --git a/src/coreclr/vm/threads.h b/src/coreclr/vm/threads.h
index 07273a9b9c2843..96d8a09f41b336 100644
--- a/src/coreclr/vm/threads.h
+++ b/src/coreclr/vm/threads.h
@@ -902,6 +902,10 @@ class Thread
     // we fire the AllocationTick event. It's only for tooling purpose.
     TypeHandle m_thAllocContextObj;
 
+#ifdef FEATURE_INTERPRETER
+    InterpThreadContext *m_pInterpThreadContext;
+#endif // FEATURE_INTERPRETER
+
 #ifndef TARGET_UNIX
 private:
     _NT_TIB *m_pTEB;
@@ -3753,7 +3757,6 @@ class Thread
 
 #ifdef FEATURE_INTERPRETER
 public:
-    InterpThreadContext *m_pInterpThreadContext;
     InterpThreadContext* GetInterpThreadContext();
     InterpThreadContext* GetOrCreateInterpThreadContext();
 #endif // FEATURE_INTERPRETER

From 449142922dea64b30daf86058179c2e9c7aadfbb Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 9 Apr 2026 02:33:25 +0000
Subject: [PATCH 2/2] Consolidate FEATURE_INTERPRETER block: move field and
 methods together near top of Thread class

Move the entire #ifdef FEATURE_INTERPRETER block (public: access specifier,
m_pInterpThreadContext field, and both method declarations) from the end of
the Thread class to just after m_thAllocContextObj. This consolidates all
interpreter-related declarations into a single #ifdef block near the top of
the class, while keeping the stable offset for m_pInterpThreadContext.

Agent-Logs-Url: https://github.com/dotnet/runtime/sessions/b426d848-547f-405d-97e3-1e21bf94368d

Co-authored-by: jkotas <6668460+jkotas@users.noreply.github.com>
---
 src/coreclr/vm/threads.h | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/src/coreclr/vm/threads.h b/src/coreclr/vm/threads.h
index 96d8a09f41b336..45c39a3354033d 100644
--- a/src/coreclr/vm/threads.h
+++ b/src/coreclr/vm/threads.h
@@ -903,7 +903,10 @@ class Thread
     TypeHandle m_thAllocContextObj;
 
 #ifdef FEATURE_INTERPRETER
+public:
     InterpThreadContext *m_pInterpThreadContext;
+    InterpThreadContext* GetInterpThreadContext();
+    InterpThreadContext* GetOrCreateInterpThreadContext();
 #endif // FEATURE_INTERPRETER
 
 #ifndef TARGET_UNIX
@@ -3754,12 +3757,6 @@ class Thread
     bool m_hasPendingActivation;
 
     friend struct ::cdac_data<Thread>;
-
-#ifdef FEATURE_INTERPRETER
-public:
-    InterpThreadContext* GetInterpThreadContext();
-    InterpThreadContext* GetOrCreateInterpThreadContext();
-#endif // FEATURE_INTERPRETER
 };
 
 template<>