Move stgpool to md subsystem, extract memory streams, eliminate VM dependencies on MD internals (#122723)

Fixes #35624

- Moved `stgpool.h`, `stgpooli.h` from `src/coreclr/inc/` to
`src/coreclr/md/inc/`
- Moved `stgpool.cpp`, `stgpooli.cpp`, `stgpoolreadonly.cpp` from
`src/coreclr/utilcode/` to `src/coreclr/md/runtime/`
- Moved `CPackedLen` struct from `stgpooli.h` to
`src/coreclr/inc/mdfileformat.h`
- Moved `CInMemoryStream` and `CGrowableStream` from `stgpool.*` to
`memorystreams.*`
- Replaced CDescPool with standalone implementation

---------

Co-authored-by: Jan Kotas <[email protected]>
Co-authored-by: Copilot <[email protected]>

Author: 3 people

src/coreclr/debug/di/module.cpp

@@ -15,7 +15,7 @@
 #include "corsym.h"
 
 #include "pedecoder.h"
-#include "stgpool.h"
+#include "memorystreams.h"
 
 //---------------------------------------------------------------------------------------
 // Initialize a new CordbModule around a Module in the target.

src/coreclr/ilasm/ilasmpch.h

@@ -23,7 +23,6 @@
 #include <stdarg.h>         // for vararg macros
 
 #include "mdfileformat.h"
-#include "stgpooli.h"
 #include "minipal/time.h"
 
 #ifdef _EXPORT

src/coreclr/inc/caparser.h

@@ -13,7 +13,7 @@
 #ifndef __CAPARSER_H__
 #define __CAPARSER_H__
 
-#include "stgpooli.h"
+#include "mdfileformat.h"
 
 class CustomAttributeParser {
 public:

src/coreclr/inc/formattype.cpp

@@ -734,10 +734,6 @@ PCCOR_SIGNATURE PrettyPrintType(
                 str = " modreq(";
             ADDCLASSTOCMOD:
                 typePtr += CorSigUncompressToken(typePtr, &tk);
-                if (IsNilToken(tk))
-                {
-                    Debug_ReportError("Nil token in custom modifier");
-                }
                 tmp.Shrink(0);
                 appendStr(&tmp, KEYWORD((char*)str));
                 PrettyPrintClass(&tmp, tk, pIMDI);

src/coreclr/inc/mdfileformat.h

@@ -261,4 +261,88 @@ class MDFormat
 
 };
 
+//*****************************************************************************
+// Helper class to pack and unpack lengths.
+//*****************************************************************************
+struct CPackedLen
+{
+    enum {MAX_LEN = 0x1fffffff};
+    static int Size(ULONG len)
+    {
+        LIMITED_METHOD_CONTRACT;
+        // Smallest.
+        if (len <= 0x7F)
+            return 1;
+        // Medium.
+        if (len <= 0x3FFF)
+            return 2;
+        // Large (too large?).
+        _ASSERTE(len <= MAX_LEN);
+        return 4;
+    }
+
+    // Get a pointer to the data, and store the length.
+    static void const *GetData(void const *pData, ULONG *pLength);
+
+    // Get the length value encoded at *pData.  Update ppData to point past data.
+    static ULONG GetLength(void const *pData, void const **ppData=0);
+
+    // Get the length value encoded at *pData, and the size of that encoded value.
+    static ULONG GetLength(void const *pData, int *pSizeOfLength);
+
+    // Pack a length at *pData; return a pointer to the next byte.
+    static void* PutLength(void *pData, ULONG len);
+
+    // This is used for just getting an encoded length, and verifies that
+    // there is no buffer or integer overflow.
+    static HRESULT SafeGetLength(       // S_OK, or error
+        void const  *pDataSource,       // First byte of length.
+        void const  *pDataSourceEnd,    // End of valid source data memory
+        ULONG       *pLength,           // Encoded value
+        void const **ppDataNext);       // Pointer immediately following encoded length
+
+    static HRESULT SafeGetLength(       // S_OK, or error
+        BYTE const  *pDataSource,       // First byte of length.
+        BYTE const  *pDataSourceEnd,    // End of valid source data memory
+        ULONG       *pLength,           // Encoded value
+        BYTE const **ppDataNext)        // Pointer immediately following encoded length
+    {
+        return SafeGetLength(
+            reinterpret_cast<void const *>(pDataSource),
+            reinterpret_cast<void const *>(pDataSourceEnd),
+            pLength,
+            reinterpret_cast<void const **>(ppDataNext));
+    }
+
+    // This performs the same tasks as GetLength above in addition to checking
+    // that the value in *pcbData does not extend *ppData beyond pDataSourceEnd
+    // and does not cause an integer overflow.
+    static HRESULT SafeGetData(
+        void const  *pDataSource,       // First byte of length.
+        void const  *pDataSourceEnd,    // End of valid source data memory
+        ULONG       *pcbData,           // Length of data
+        void const **ppData);           // Start of data
+
+    static HRESULT SafeGetData(
+        BYTE const  *pDataSource,       // First byte of length.
+        BYTE const  *pDataSourceEnd,    // End of valid source data memory
+        ULONG       *pcbData,           // Length of data
+        BYTE const **ppData)            // Start of data
+    {
+        return SafeGetData(
+            reinterpret_cast<void const *>(pDataSource),
+            reinterpret_cast<void const *>(pDataSourceEnd),
+            pcbData,
+            reinterpret_cast<void const **>(ppData));
+    }
+
+    // This is the same as GetData above except it takes a byte count instead
+    // of pointer to determine the source data length.
+    static HRESULT SafeGetData(         // S_OK, or error
+        void const  *pDataSource,       // First byte of data
+        ULONG        cbDataSource,      // Count of valid bytes in data source
+        ULONG       *pcbData,           // Length of data
+        void const **ppData);           // Start of data
+};
+
 #endif // __MDFileFormat_h__

src/coreclr/inc/memoryrange.h

@@ -10,6 +10,7 @@
 #define _memory_range_h
 
 #include "daccess.h"
+#include "contract.h"
 
 // MemoryRange is a descriptor of a memory range. This groups (pointer + size).
 //
@@ -49,8 +50,6 @@ class MemoryRange
 
     // Note: use compiler-default copy ctor and assignment operator
 
-
-
     // Check whether a pointer is in the memory range represented by this instance.
     BOOL IsInRange(PTR_VOID pAddress) const
     {
@@ -94,4 +93,3 @@ class MemoryRange
 typedef ArrayDPTR(MemoryRange) ARRAY_PTR_MemoryRange;
 
 #endif // _memory_range_h
-