Patches: add tls patch from upstream repo

Author: maximmenshikov

patches/bflat-runtime/16_tls_opt.patch

@@ -0,0 +1,80 @@
+From fa6e00abe9be4a451d81a29309c933435db8fe40 Mon Sep 17 00:00:00 2001
+From: Adeel Mujahid <3840695+am11@users.noreply.github.com>
+Date: Sat, 15 Nov 2025 22:15:48 +0200
+Subject: [PATCH] Disable TLS optimization for musl riscv64 (#121662)
+
+On linux-musl-riscv64, when corehost (dotnet) dlopen()s libcoreclr, we
+get:
+
+> \# dotnet --version
+> Failed to load
+/root/.dotnet/shared/Microsoft.NETCore.App/10.0.0-rtm.25564.199/libcoreclr.so,
+error: Error relocating
+/root/.dotnet/shared/Microsoft.NETCore.App/10.0.0-rtm.25564.199/libcoreclr.so:
+Uq???&?J?N?R?V?Z? .????: initial-exec TLS resolves to dynamic definition
+in
+/root/.dotnet/shared/Microsoft.NETCore.App/10.0.0-rtm.25564.199/libcoreclr.so
+Failed to bind to CoreCLR at
+'/root/.dotnet/shared/Microsoft.NETCore.App/10.0.0-rtm.25564.199/'
+Failed to create CoreCLR, HRESULT: 0x80008088
+
+musl maintainer described the issue on this golang thread:
+https://github.com/golang/go/issues/54805#issuecomment-1253972041. When
+I tried
+`LD_PRELOAD=/root/.dotnet/shared/Microsoft.NETCore.App/10.0.0-rtm.25564.199/libcoreclr.so
+dotnet --version`, it started working and SDK started working.
+
+By disabling the optimization as we have done for linux-musl-arm64 and
+removing `la.tls.ie` from binary works without the `LD_PRELOAD` hack.
+
+---------
+
+Co-authored-by: Jan Kotas <jkotas@microsoft.com>
+---
+ src/coreclr/vm/riscv64/asmhelpers.S | 4 ++++
+ src/coreclr/vm/threadstatics.cpp    | 5 +++++
+ 2 files changed, 9 insertions(+)
+
+diff --git a/src/coreclr/vm/riscv64/asmhelpers.S b/src/coreclr/vm/riscv64/asmhelpers.S
+index 1c03436880c0cc..e9c049f1b64197 100644
+--- a/src/coreclr/vm/riscv64/asmhelpers.S
++++ b/src/coreclr/vm/riscv64/asmhelpers.S
+@@ -844,10 +844,14 @@ LEAF_END JIT_PatchpointForced, _TEXT
+ // size_t GetThreadStaticsVariableOffset()
+ 
+ // Load offset of native thread local variable `t_ThreadStatics` in TCB and return it in `a0` register.
++#if !defined(TARGET_LINUX_MUSL)
++// Uses initial-exec TLS model which is faster but incompatible with musl's dynamic loading.
++// On musl, this function is not compiled and the optimization is disabled in threadstatics.cpp.
+ LEAF_ENTRY GetThreadStaticsVariableOffset, _TEXT
+     la.tls.ie   a0, t_ThreadStatics
+     EPILOG_RETURN
+ LEAF_END GetThreadStaticsVariableOffset, _TEXT
++#endif // !TARGET_LINUX_MUSL
+ 
+ LEAF_ENTRY JIT_PollGC, _TEXT
+         PREPARE_EXTERNAL_VAR g_TrapReturningThreads, t0
+diff --git a/src/coreclr/vm/threadstatics.cpp b/src/coreclr/vm/threadstatics.cpp
+index 5847cc5c13bb47..0f45787cd8f92b 100644
+--- a/src/coreclr/vm/threadstatics.cpp
++++ b/src/coreclr/vm/threadstatics.cpp
+@@ -916,6 +916,8 @@ bool CanJITOptimizeTLSAccess()
+     // Optimization is disabled for linux/x86
+ #elif defined(TARGET_LINUX_MUSL) && defined(TARGET_ARM64)
+     // Optimization is disabled for linux musl arm64
++#elif defined(TARGET_LINUX_MUSL) && defined(TARGET_RISCV64)
++    // Optimization is disabled for linux musl riscv64
+ #elif defined(TARGET_FREEBSD) && defined(TARGET_ARM64)
+     // Optimization is disabled for FreeBSD/arm64
+ #elif defined(TARGET_ANDROID)
+@@ -1095,7 +1097,10 @@ void GetThreadLocalStaticBlocksInfo(CORINFO_THREAD_STATIC_BLOCKS_INFO* pInfo)
+     // For Linux arm64/loongarch64/riscv64, just get the offset of thread static variable, and during execution,
+     // this offset, arm64 taken from trpid_elp0 system register gives back the thread variable address.
+     // this offset, loongarch64 taken from $tp register gives back the thread variable address.
++#if !(defined(TARGET_LINUX_MUSL) && defined(TARGET_RISCV64))
++    // On musl riscv64, this optimization is disabled due to initial-exec TLS incompatibility.
+     threadStaticBaseOffset = GetThreadStaticsVariableOffset();
++#endif
+ 
+ #else
+     _ASSERTE_MSG(false, "Unsupported scenario of optimizing TLS access on Linux Arm32/x86 and Android");