Improve likely class handling for pgo (#51284)

- Move processing of likely class histogram into the JIT
- Fix cases where the devirtualization logic in crossgen2 behaved incorrectly in the presence of likely class histogram data
- Pre-process histogram at crossgen2 time to reduce the size of the pgo data
  - This removes 3/4 of the data from System.Private.CoreLib

8 files changed, 1 insertions, 111 deletions

diff --git a/src/coreclr/ToolBox/superpmi/superpmi-shared/agnostic.h b/src/coreclr/ToolBox/superpmi/superpmi-shared/agnostic.h
index 44f3f799431..59cc7857f4c 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi-shared/agnostic.h
+++ b/src/coreclr/ToolBox/superpmi/superpmi-shared/agnostic.h
@@ -493,20 +493,6 @@ struct Agnostic_GetPgoInstrumentationResults
     DWORD result;
 };
 
-struct Agnostic_GetLikelyClass
-{
-    DWORDLONG ftnHnd;
-    DWORDLONG baseHnd;
-    DWORD     ilOffset;
-};
-
-struct Agnostic_GetLikelyClassResult
-{
-    DWORDLONG classHnd;
-    DWORD     likelihood;
-    DWORD     numberOfClasses;
-};
-
 struct Agnostic_GetProfilingHandle
 {
     DWORD     bHookFunction;
diff --git a/src/coreclr/ToolBox/superpmi/superpmi-shared/lwmlist.h b/src/coreclr/ToolBox/superpmi/superpmi-shared/lwmlist.h
index 71f9eca564a..338a4eb935e 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi-shared/lwmlist.h
+++ b/src/coreclr/ToolBox/superpmi/superpmi-shared/lwmlist.h
@@ -99,7 +99,6 @@ LWM(GetJitFlags, DWORD, DD)
 LWM(GetJitTimeLogFilename, DWORD, DWORD)
 LWM(GetJustMyCodeHandle, DWORDLONG, DLDL)
 LWM(GetLazyStringLiteralHelper, DWORDLONG, DWORD)
-LWM(GetLikelyClass, Agnostic_GetLikelyClass, Agnostic_GetLikelyClassResult)
 LWM(GetLocationOfThisType, DWORDLONG, Agnostic_CORINFO_LOOKUP_KIND)
 LWM(IsJitIntrinsic, DWORDLONG, DWORD)
 LWM(GetMethodAttribs, DWORDLONG, DWORD)
diff --git a/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.cpp b/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.cpp
index 0654207f281..a4badbfcae3 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.cpp
+++ b/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.cpp
@@ -5558,48 +5558,6 @@ HRESULT MethodContext::repGetPgoInstrumentationResults(CORINFO_METHOD_HANDLE ftn
     return result;
 }
 
-void MethodContext::recGetLikelyClass(CORINFO_METHOD_HANDLE ftnHnd, CORINFO_CLASS_HANDLE baseHnd, UINT32 ilOffset, CORINFO_CLASS_HANDLE result, UINT32* pLikelihood, UINT32* pNumberOfClasses)
-{
-    if (GetLikelyClass == nullptr)
-        GetLikelyClass = new LightWeightMap<Agnostic_GetLikelyClass, Agnostic_GetLikelyClassResult>();
-
-    Agnostic_GetLikelyClass key;
-    ZeroMemory(&key, sizeof(Agnostic_GetLikelyClass));
-
-    key.ftnHnd = CastHandle(ftnHnd);
-    key.baseHnd = CastHandle(baseHnd);
-    key.ilOffset = (DWORD) ilOffset;
-
-    Agnostic_GetLikelyClassResult value;
-    ZeroMemory(&value, sizeof(Agnostic_GetLikelyClassResult));
-    value.classHnd = CastHandle(result);
-    value.likelihood = *pLikelihood;
-    value.numberOfClasses = *pNumberOfClasses;
-
-    GetLikelyClass->Add(key, value);
-    DEBUG_REC(dmpGetLikelyClass(key, value));
-}
-void MethodContext::dmpGetLikelyClass(const Agnostic_GetLikelyClass& key, const Agnostic_GetLikelyClassResult& value)
-{
-    printf("GetLikelyClass key ftn-%016llX base-%016llX il-%u, class-%016llX likelihood-%u numberOfClasses-%u",
-        key.ftnHnd, key.baseHnd, key.ilOffset, value.classHnd, value.likelihood, value.numberOfClasses);
-}
-CORINFO_CLASS_HANDLE MethodContext::repGetLikelyClass(CORINFO_METHOD_HANDLE ftnHnd, CORINFO_CLASS_HANDLE baseHnd, UINT32 ilOffset, UINT32* pLikelihood, UINT32* pNumberOfClasses)
-{
-    Agnostic_GetLikelyClass key;
-    ZeroMemory(&key, sizeof(Agnostic_GetLikelyClass));
-    key.ftnHnd = CastHandle(ftnHnd);
-    key.baseHnd = CastHandle(baseHnd);
-    key.ilOffset = (DWORD) ilOffset;
-
-    Agnostic_GetLikelyClassResult value = GetLikelyClass->Get(key);
-    DEBUG_REP(dmpGetLikelyClass(key, value));
-
-    *pLikelihood = value.likelihood;
-    *pNumberOfClasses = value.numberOfClasses;
-    return (CORINFO_CLASS_HANDLE) value.classHnd;
-}
-
 void MethodContext::recMergeClasses(CORINFO_CLASS_HANDLE cls1, CORINFO_CLASS_HANDLE cls2, CORINFO_CLASS_HANDLE result)
 {
     if (MergeClasses == nullptr)
diff --git a/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.h b/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.h
index 69837068f23..1fe4c95fc05 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.h
+++ b/src/coreclr/ToolBox/superpmi/superpmi-shared/methodcontext.h
@@ -701,10 +701,6 @@ public:
     void dmpGetPgoInstrumentationResults(DWORDLONG key, const Agnostic_GetPgoInstrumentationResults& value);
     HRESULT repGetPgoInstrumentationResults(CORINFO_METHOD_HANDLE ftnHnd, ICorJitInfo::PgoInstrumentationSchema** pSchema, UINT32* pCountSchemaItems, BYTE** pInstrumentationData);
 
-    void recGetLikelyClass(CORINFO_METHOD_HANDLE ftnHnd, CORINFO_CLASS_HANDLE  baseHnd, UINT32 ilOffset, CORINFO_CLASS_HANDLE classHnd, UINT32* pLikelihood, UINT32* pNumberOfClasses);
-    void dmpGetLikelyClass(const Agnostic_GetLikelyClass& key, const Agnostic_GetLikelyClassResult& value);
-    CORINFO_CLASS_HANDLE repGetLikelyClass(CORINFO_METHOD_HANDLE ftnHnd, CORINFO_CLASS_HANDLE  baseHnd, UINT32 ilOffset, UINT32* pLikelihood, UINT32* pNumberOfClasses);
-
     void recMergeClasses(CORINFO_CLASS_HANDLE cls1, CORINFO_CLASS_HANDLE cls2, CORINFO_CLASS_HANDLE result);
     void dmpMergeClasses(DLDL key, DWORDLONG value);
     CORINFO_CLASS_HANDLE repMergeClasses(CORINFO_CLASS_HANDLE cls1, CORINFO_CLASS_HANDLE cls2);
@@ -1002,7 +998,7 @@ enum mcPackets
     Packet_GetJitFlags                                   = 154, // Added 2/3/2016
     Packet_GetJitTimeLogFilename                         = 67,
     Packet_GetJustMyCodeHandle                           = 68,
-    Packet_GetLikelyClass                                = 182, // Added 9/27/2020
+    Retired10                                            = 182, // Added 9/27/2020 // was Packet_GetLikelyClass
     Packet_GetLocationOfThisType                         = 69,
     Packet_IsJitIntrinsic                                = 192,
     Packet_GetMethodAttribs                              = 70,
diff --git a/src/coreclr/ToolBox/superpmi/superpmi-shim-collector/icorjitinfo.cpp b/src/coreclr/ToolBox/superpmi/superpmi-shim-collector/icorjitinfo.cpp
index 281533e4aff..9b799a18040 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi-shim-collector/icorjitinfo.cpp
+++ b/src/coreclr/ToolBox/superpmi/superpmi-shim-collector/icorjitinfo.cpp
@@ -2084,21 +2084,6 @@ HRESULT interceptor_ICJI::getPgoInstrumentationResults(CORINFO_METHOD_HANDLE
     return temp;
 }
 
-// Get the likely implementing class for a virtual call or interface call made by ftnHnd
-// at the indicated IL offset. baseHnd is the interface class or base class for the method
-// being called.
-CORINFO_CLASS_HANDLE interceptor_ICJI::getLikelyClass(CORINFO_METHOD_HANDLE ftnHnd,
-                                                      CORINFO_CLASS_HANDLE  baseHnd,
-                                                      uint32_t              ilOffset,
-                                                      uint32_t*             pLikelihood,
-                                                      uint32_t*             pNumberOfClasses)
-{
-    mc->cr->AddCall("getLikelyClass");
-    CORINFO_CLASS_HANDLE result = original_ICorJitInfo->getLikelyClass(ftnHnd, baseHnd, ilOffset, pLikelihood, pNumberOfClasses);
-    mc->recGetLikelyClass(ftnHnd, baseHnd, ilOffset, result, pLikelihood, pNumberOfClasses);
-    return result;
-}
-
 // Associates a native call site, identified by its offset in the native code stream, with
 // the signature information and method handle the JIT used to lay out the call site. If
 // the call site has no signature information (e.g. a helper call) or has no method handle
diff --git a/src/coreclr/ToolBox/superpmi/superpmi-shim-counter/icorjitinfo.cpp b/src/coreclr/ToolBox/superpmi/superpmi-shim-counter/icorjitinfo.cpp
index d5ee05be454..918d18893f9 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi-shim-counter/icorjitinfo.cpp
+++ b/src/coreclr/ToolBox/superpmi/superpmi-shim-counter/icorjitinfo.cpp
@@ -1352,17 +1352,6 @@ JITINTERFACE_HRESULT interceptor_ICJI::allocPgoInstrumentationBySchema(
     return original_ICorJitInfo->allocPgoInstrumentationBySchema(ftnHnd, pSchema, countSchemaItems, pInstrumentationData);
 }
 
-CORINFO_CLASS_HANDLE interceptor_ICJI::getLikelyClass(
-          CORINFO_METHOD_HANDLE ftnHnd,
-          CORINFO_CLASS_HANDLE baseHnd,
-          uint32_t ilOffset,
-          uint32_t* pLikelihood,
-          uint32_t* pNumberOfClasses)
-{
-    mcs->AddCall("getLikelyClass");
-    return original_ICorJitInfo->getLikelyClass(ftnHnd, baseHnd, ilOffset, pLikelihood, pNumberOfClasses);
-}
-
 void interceptor_ICJI::recordCallSite(
           uint32_t instrOffset,
           CORINFO_SIG_INFO* callSig,
diff --git a/src/coreclr/ToolBox/superpmi/superpmi-shim-simple/icorjitinfo.cpp b/src/coreclr/ToolBox/superpmi/superpmi-shim-simple/icorjitinfo.cpp
index 3aed50b5b51..19cf1f8a71e 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi-shim-simple/icorjitinfo.cpp
+++ b/src/coreclr/ToolBox/superpmi/superpmi-shim-simple/icorjitinfo.cpp
@@ -1185,16 +1185,6 @@ JITINTERFACE_HRESULT interceptor_ICJI::allocPgoInstrumentationBySchema(
     return original_ICorJitInfo->allocPgoInstrumentationBySchema(ftnHnd, pSchema, countSchemaItems, pInstrumentationData);
 }
 
-CORINFO_CLASS_HANDLE interceptor_ICJI::getLikelyClass(
-          CORINFO_METHOD_HANDLE ftnHnd,
-          CORINFO_CLASS_HANDLE baseHnd,
-          uint32_t ilOffset,
-          uint32_t* pLikelihood,
-          uint32_t* pNumberOfClasses)
-{
-    return original_ICorJitInfo->getLikelyClass(ftnHnd, baseHnd, ilOffset, pLikelihood, pNumberOfClasses);
-}
-
 void interceptor_ICJI::recordCallSite(
           uint32_t instrOffset,
           CORINFO_SIG_INFO* callSig,
diff --git a/src/coreclr/ToolBox/superpmi/superpmi/icorjitinfo.cpp b/src/coreclr/ToolBox/superpmi/superpmi/icorjitinfo.cpp
index 4f86025dfc8..18dac3b1db3 100644
--- a/src/coreclr/ToolBox/superpmi/superpmi/icorjitinfo.cpp
+++ b/src/coreclr/ToolBox/superpmi/superpmi/icorjitinfo.cpp
@@ -1825,19 +1825,6 @@ HRESULT MyICJI::getPgoInstrumentationResults(CORINFO_METHOD_HANDLE      ftnHnd,
     return jitInstance->mc->repGetPgoInstrumentationResults(ftnHnd, pSchema, pCountSchemaItems, pInstrumentationData);
 }
 
-// Get the likely implementing class for a virtual call or interface call made by ftnHnd
-// at the indicated IL offset. baseHnd is the interface class or base class for the method
-// being called.
-CORINFO_CLASS_HANDLE MyICJI::getLikelyClass(CORINFO_METHOD_HANDLE ftnHnd,
-                                            CORINFO_CLASS_HANDLE  baseHnd,
-                                            uint32_t              ilOffset,
-                                            uint32_t*             pLikelihood,
-                                            uint32_t*             pNumberOfClasses)
-{
-    jitInstance->mc->cr->AddCall("getLikelyClass");
-    return jitInstance->mc->repGetLikelyClass(ftnHnd, baseHnd, ilOffset, pLikelihood, pNumberOfClasses);
-}
-
 // Associates a native call site, identified by its offset in the native code stream, with
 // the signature information and method handle the JIT used to lay out the call site. If
 // the call site has no signature information (e.g. a helper call) or has no method handle