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-rw-r--r--src/utilcode/tls.cpp271
1 files changed, 0 insertions, 271 deletions
diff --git a/src/utilcode/tls.cpp b/src/utilcode/tls.cpp
deleted file mode 100644
index cb6934fd0b..0000000000
--- a/src/utilcode/tls.cpp
+++ /dev/null
@@ -1,271 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for more information.
-/* TLS.CPP:
- *
-
- *
- * Encapsulates TLS access for maximum performance.
- *
- */
-
-#include "stdafx.h"
-
-#include "unsafe.h"
-#include "tls.h"
-#include "contract.h"
-#include "corerror.h"
-#include "ex.h"
-#include "clrhost.h"
-
-#ifndef SELF_NO_HOST
-#include "clrconfig.h"
-#endif
-
-#include "clrnt.h"
-
-#ifndef SELF_NO_HOST
-
-//---------------------------------------------------------------------------
-// Win95 and WinNT store the TLS in different places relative to the
-// fs:[0]. This api reveals which. Can also return TLSACCESS_GENERIC if
-// no info is available about the Thread location (you have to use the TlsGetValue
-// api.) This is intended for use by stub generators that want to inline TLS
-// access.
-//---------------------------------------------------------------------------
-TLSACCESSMODE GetTLSAccessMode(DWORD tlsIndex)
-{
- // Static contracts because this is used by contract infrastructure
- STATIC_CONTRACT_NOTHROW;
- STATIC_CONTRACT_GC_NOTRIGGER;
-
- TLSACCESSMODE tlsAccessMode = TLSACCESS_GENERIC;
-
-#ifdef _DEBUG
- // Debug builds allow user to throw a switch to force use of the generic
- // (non-optimized) Thread/AppDomain getters. Even if the user doesn't throw
- // the switch, force tests to go down the generic getter code path about 1% of the
- // time so it's exercised a couple dozen times during each devbvt run.
- if ((CLRConfig::GetConfigValue(CLRConfig::EXTERNAL_UseGenericTlsGetters) != 0) || DbgRandomOnExe(.01))
- return TLSACCESS_GENERIC;
-#endif
-
- if (tlsIndex < TLS_MINIMUM_AVAILABLE)
- {
- tlsAccessMode = TLSACCESS_WNT;
- }
- else
- if (tlsIndex < (TLS_MINIMUM_AVAILABLE + TLS_EXPANSION_SLOTS))
- {
- // Expansion slots are lazily created at the first call to
- // TlsGetValue on a thread, and the code we generate
- // assumes that the expansion slots will exist.
- //
- // <TODO> On newer flavors of NT we could use the vectored
- // exception handler to take the AV, call TlsGetValue, and
- // resume execution at the start of the getter. </TODO>
- tlsAccessMode = TLSACCESS_GENERIC;//TLSACCESS_WNT_HIGH;
- }
- else
- {
- //
- // If the app verifier is enabled, TLS indices
- // are faked to help detect invalid handle use.
- //
- }
-
- return tlsAccessMode;
-}
-
-//---------------------------------------------------------------------------
-// Creates a platform-optimized version of TlsGetValue compiled
-// for a particular index. Can return NULL.
-//---------------------------------------------------------------------------
-// A target for the optimized getter can be passed in, this is
-// useful so that code can avoid an indirect call for the GetThread
-// and GetAppDomain calls for instance. If NULL is passed then
-// we will allocate from the executeable heap.
-POPTIMIZEDTLSGETTER MakeOptimizedTlsGetter(DWORD tlsIndex, LPVOID pBuffer, SIZE_T cbBuffer, POPTIMIZEDTLSGETTER pGenericImpl, BOOL fForceGeneric)
-{
- // Static contracts because this is used by contract infrastructure
- STATIC_CONTRACT_NOTHROW;
- STATIC_CONTRACT_GC_NOTRIGGER;
-
- ARM_ONLY(pBuffer = ThumbCodeToDataPointer<BYTE*>(pBuffer));
-
- // Buffer that should be big enough to encode the TLS getter on any reasonable platform
- TADDR patch[4 INDEBUG(+4 /* last error trashing */)];
-
- PBYTE pPatch = (PBYTE)&patch;
-
- TLSACCESSMODE mode = fForceGeneric ? TLSACCESS_GENERIC : GetTLSAccessMode(tlsIndex);
-
-#if defined(_DEBUG)
- if (mode != TLSACCESS_GENERIC)
- {
- //
- // Trash last error in debug builds
- //
-
-#ifdef _TARGET_X86_
- *((DWORD*) (pPatch + 0)) = 0x05c764; // mov dword ptr fs:[offsetof(TEB, LastErrorValue)], LAST_ERROR_TRASH_VALUE
- *((DWORD*) (pPatch + 3)) = offsetof(TEB, LastErrorValue);
- *((DWORD*) (pPatch + 7)) = LAST_ERROR_TRASH_VALUE;
- pPatch += 11;
-#endif // _TARGET_X86_
-
-#ifdef _TARGET_AMD64_
- // iDNA doesn't like writing directly to gs:[nn]
- *((UINT64*)(pPatch + 0)) = 0x25048b4865; // mov rax, gs:[offsetof(TEB, NtTib.Self)]
- *((DWORD*) (pPatch + 5)) = offsetof(TEB, NtTib.Self);
- *((WORD*) (pPatch + 9)) = 0x80c7; // mov dword ptr [rax + offsetof(TEB, LastErrorValue)], LAST_ERROR_TRASH_VALUE
- *((DWORD*) (pPatch + 11)) = offsetof(TEB, LastErrorValue);
- *((DWORD*) (pPatch + 15)) = LAST_ERROR_TRASH_VALUE;
- pPatch += 19;
-#endif
- }
-#endif // _DEBUG
-
- switch (mode)
- {
-#ifdef _TARGET_X86_
- case TLSACCESS_WNT:
- *((WORD*) (pPatch + 0)) = 0xa164; // mov eax, fs:[IMM32]
- *((DWORD*) (pPatch + 2)) = offsetof(TEB, TlsSlots) + tlsIndex * sizeof(void*);
- *((BYTE*) (pPatch + 6)) = 0xc3; // retn
- pPatch += 7;
- break;
-
- case TLSACCESS_GENERIC:
- if (pGenericImpl == NULL)
- return NULL;
-
- _ASSERTE(pBuffer != NULL);
- *((BYTE*) (pPatch + 0)) = 0xE9; // jmp pGenericImpl
- TADDR rel32 = ((TADDR)pGenericImpl - ((TADDR)pBuffer + 1 + sizeof(INT32)));
- *((INT32*) (pPatch + 1)) = (INT32)rel32;
- pPatch += 5;
- break;
-#endif // _TARGET_X86_
-
-#ifdef _TARGET_AMD64_
- case TLSACCESS_WNT:
- *((UINT64*)(pPatch + 0)) = 0x25048b4865; // mov rax, gs:[IMM32]
- *((DWORD*) (pPatch + 5)) = offsetof(TEB, TlsSlots) + (tlsIndex * sizeof(void*));
- *((BYTE*) (pPatch + 9)) = 0xc3; // return
- pPatch += 10;
- break;
-
- case TLSACCESS_GENERIC:
- if (pGenericImpl == NULL)
- return NULL;
-
- _ASSERTE(pBuffer != NULL);
- *((BYTE*) (pPatch + 0)) = 0xE9; // jmp pGenericImpl
- TADDR rel32 = ((TADDR)pGenericImpl - ((TADDR)pBuffer + 1 + sizeof(INT32)));
- _ASSERTE((INT64)(INT32)rel32 == (INT64)rel32);
- *((INT32*) (pPatch + 1)) = (INT32)rel32;
- pPatch += 5;
-
- *pPatch++ = 0xCC; // Make sure there is full 8 bytes worth of data
- *pPatch++ = 0xCC;
- *pPatch++ = 0xCC;
- break;
-
-#endif // _TARGET_AMD64_
-
-#ifdef _TARGET_ARM_
- case TLSACCESS_WNT:
- {
- WORD slotOffset = (WORD)(offsetof(TEB, TlsSlots) + tlsIndex * sizeof(void*));
- _ASSERTE(slotOffset < 4096);
-
- WORD *pInstr = (WORD*)pPatch;
-
- *pInstr++ = 0xee1d; // mrc p15, 0, r0, c13, c0, 2
- *pInstr++ = 0x0f50;
- *pInstr++ = 0xf8d0; // ldr r0, [r0, #slotOffset]
- *pInstr++ = slotOffset;
- *pInstr++ = 0x4770; // bx lr
-
- pPatch = (PBYTE)pInstr;
- }
- break;
-
- case TLSACCESS_GENERIC:
- {
- if (pGenericImpl == NULL)
- return NULL;
-
- _ASSERTE(pBuffer != NULL);
-
- *(DWORD *)pPatch = 0x9000F000; // b pGenericImpl
- PutThumb2BlRel24((WORD*)pPatch, (TADDR)pGenericImpl - ((TADDR)pBuffer + 4 + THUMB_CODE));
-
- pPatch += 4;
- }
- break;
-#endif // _TARGET_ARM_
- }
-
- SIZE_T cbCode = (TADDR)pPatch - (TADDR)&patch;
- _ASSERTE(cbCode <= sizeof(patch));
-
- if (pBuffer != NULL)
- {
- _ASSERTE_ALL_BUILDS("clr/src/utilcode/tls.cpp", cbCode <= cbBuffer);
-
- // We assume that the first instruction of the buffer is a short jump to dummy helper
- // that can be atomically overwritten to avoid races with other threads executing the code.
- // It is the same basic technique as hot patching.
-
- // Assert on all builds to make sure that retail optimizations are not affecting the alignment.
- _ASSERTE_ALL_BUILDS("clr/src/utilcode/tls.cpp", IS_ALIGNED((void*)pBuffer, sizeof(TADDR)));
-
- // Size of short jump that gets patched last.
- if (cbCode > sizeof(TADDR))
- {
- memcpy((BYTE *)pBuffer + sizeof(TADDR), &patch[1], cbCode - sizeof(TADDR));
- FlushInstructionCache(GetCurrentProcess(), (BYTE *)pBuffer + sizeof(TADDR), cbCode - sizeof(TADDR));
- }
-
- // Make sure that the the dummy implementation still works.
- _ASSERTE(((POPTIMIZEDTLSGETTER)ARM_ONLY(DataPointerToThumbCode<BYTE*>)(pBuffer))() == NULL);
-
- // It is important for this write to happen atomically
- VolatileStore<TADDR>((TADDR *)pBuffer, patch[0]);
-
- FlushInstructionCache(GetCurrentProcess(), (BYTE *)pBuffer, sizeof(TADDR));
- }
- else
- {
- pBuffer = (BYTE*) new (executable, nothrow) BYTE[cbCode];
- if (pBuffer == NULL)
- return NULL;
-
- memcpy(pBuffer, &patch, cbCode);
-
- FlushInstructionCache(GetCurrentProcess(), pBuffer, cbCode);
- }
-
- return (POPTIMIZEDTLSGETTER)ARM_ONLY(DataPointerToThumbCode<BYTE*>)(pBuffer);
-}
-
-
-//---------------------------------------------------------------------------
-// Frees a function created by MakeOptimizedTlsGetter().
-//---------------------------------------------------------------------------
-VOID FreeOptimizedTlsGetter(POPTIMIZEDTLSGETTER pOptimizedTlsGetter)
-{
- // Static contracts because this is used by contract infrastructure
- STATIC_CONTRACT_NOTHROW;
- STATIC_CONTRACT_GC_NOTRIGGER;
-
- BYTE* pGetter = (BYTE*)pOptimizedTlsGetter;
-#ifdef _TARGET_ARM_
- pGetter = ThumbCodeToDataPointer<BYTE*>(pGetter);
-#endif
- DeleteExecutable(pGetter);
-}
-
-#endif // !SELF_NO_HOST
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-07 01:44:46 +0000