GCInfo: Support versioning.

This change enables the VM to support multiple versions GCInfo concurrently.
This is necessary in light of upcoming work to add ReturnType and other
modifications to the GCInfo format -- so that existing ReadyToRun images
will continue to run correctly.

The version# is not stored in the GcInfo structure -- because it is
wasteful to store the version once for every method. Instead, it is
tracked per range-section of generated/loaded methods.

The GCInfo version is computed as:
1) The current GCINFO_VERSION for JITted and Ngened images
2) A function of the Ready-to-run major version stored in READYTORUN_HEADER
   for ready-to-run images. ReadyToRunJitManager::JitTokenToGCInfoVersion()
   provides the GcInfo version for any Method. Currently, there's only one
   version of GCInfo.

An abstraction GCInfoToken is added to the GcInfo interface, which tracks the
{GcInfo, Version} pair in-memory. Several GcInfo APIs are
modified to use GCInfoToken in place of GcInfo pointers.

Notes:
1) SOS GcDump: The GCDump API has separate dump routines for Header and the
pointer-liveness information (DumpGCTable and DumpGCHeader) each of which
advance a pointer to the GCInfo block. These APIs are not changed to
recieve a GCInfoToken in place of the GcInfo block pointer. Instead, they
recieve the GcInfo version at the time of construction.
2) Some routines that are specific to x86 gcInfo (ex: crackMethodInfoHdr)
are not yet updated to use versioning, since the development plan is to
update the Non-x86 GcInfo structure first.
3) The x86 specific structs defining GcInfo headers are moved to GcInfoTypes.h,
along with the non-x86 GcInfo type definitions.

1 files changed, 8 insertions, 7 deletions

diff --git a/src/inc/gcdump.h b/src/inc/gcdump.h
index aded6bb102..cd73940ded 100644
--- a/src/inc/gcdump.h
+++ b/src/inc/gcdump.h
@@ -17,7 +17,7 @@
 #define __GCDUMP_H__
 /*****************************************************************************/
 
-#include "gcinfo.h"     // For InfoHdr
+#include "gcinfotypes.h"     // For InfoHdr
 
 #ifndef FASTCALL
 #ifndef FEATURE_PAL
@@ -32,7 +32,8 @@ class GCDump
 {
 public:
 
-    GCDump                          (bool           encBytes     = true, 
+    GCDump                          (UINT32         gcInfoVersion,
+                                     bool           encBytes     = true, 
                                      unsigned       maxEncBytes  = 5, 
                                      bool           dumpCodeOffs = true);
 
@@ -44,7 +45,7 @@ public:
      * Return value     : Size in bytes of the header encoding
      */
 
-    unsigned FASTCALL   DumpInfoHdr (PTR_CBYTE      table,
+    unsigned FASTCALL   DumpInfoHdr (PTR_CBYTE      gcInfoBlock,
                                      InfoHdr    *   header,         /* OUT */
                                      unsigned   *   methodSize,     /* OUT */
                                      bool           verifyGCTables = false);
@@ -52,13 +53,12 @@ public:
 
     /*-------------------------------------------------------------------------
      * Dumps the GC tables to 'stdout'
-     * table            : Ptr to the start of the table part of the GC info.
-     *                      This immediately follows the GCinfo header
+     * table            : The GCInfoToken
      * verifyGCTables   : If the JIT has been compiled with VERIFY_GC_TABLES
      * Return value     : Size in bytes of the GC table encodings
      */
 
-    size_t   FASTCALL   DumpGCTable (PTR_CBYTE      table,
+    size_t   FASTCALL   DumpGCTable (PTR_CBYTE      gcInfoBlock,
 #ifdef _TARGET_X86_
                                      const InfoHdr& header,
 #endif
@@ -79,6 +79,7 @@ public:
 public:
 	typedef void (*printfFtn)(const char* fmt, ...);
 	printfFtn gcPrintf;	
+    UINT32              gcInfoVersion;
     //-------------------------------------------------------------------------
 protected:
 
@@ -89,7 +90,7 @@ protected:
 
     /* Helper methods */
 
-    PTR_CBYTE           DumpEncoding(PTR_CBYTE      table, 
+    PTR_CBYTE           DumpEncoding(PTR_CBYTE      gcInfoBlock,
                                      int            cDumpBytes);
     void                DumpOffset  (unsigned       o);
     void                DumpOffsetEx(unsigned       o);