Add compile-time and run-time methods to obtain Vector<T> byte length

src/coreclr/inc/corinfo.h

@@ -936,6 +936,7 @@ enum CorInfoClassId
     CLASSID_STRING,
     CLASSID_ARGUMENT_HANDLE,
     CLASSID_RUNTIME_TYPE,
+    CLASSID_NUMERICS_VECTORT,
 };
 
 enum CorInfoInline

src/coreclr/inc/jiteeversionguid.h

@@ -37,11 +37,11 @@
 
 #include <minipal/guid.h>
 
-constexpr GUID JITEEVersionIdentifier = { /* 12e9a95b-fa7c-43ed-a339-fbbc6e74bffa */
-    0x12e9a95b,
-    0xfa7c,
-    0x43ed,
-    {0xa3, 0x39, 0xfb, 0xbc, 0x6e, 0x74, 0xbf, 0xfa}
+constexpr GUID JITEEVersionIdentifier = { /* daa88390-808f-4164-908c-8635f9c8282c */
+    0xdaa88390,
+    0x808f,
+    0x4164,
+    {0x90, 0x8c, 0x86, 0x35, 0xf9, 0xc8, 0x28, 0x2c}
   };
 
 #endif // JIT_EE_VERSIONING_GUID_H

src/coreclr/jit/compiler.h

@@ -5441,6 +5441,8 @@ class Compiler
 #endif // TARGET_ARM64
 
 #endif // FEATURE_HW_INTRINSICS
+    GenTree* evalVectorCount(CORINFO_CLASS_HANDLE vectorHandle, var_types simdBaseType);
+
     GenTree* impArrayAccessIntrinsic(CORINFO_CLASS_HANDLE clsHnd,
                                      CORINFO_SIG_INFO*    sig,
                                      int                  memberRef,
@@ -10230,9 +10232,20 @@ class Compiler
     // Get the number of elements of baseType of SIMD vector given by its size and baseType
     static int getSIMDVectorLength(unsigned simdSize, var_types baseType);
 
-    // Get the number of bytes in a System.Numeric.Vector<T> for the current compilation.
+    // ---------------------------------------------------------------------------------------
+    // getCompileTimeVectorTByteLength: Get the number of bytes in a System.Numeric.Vector<T>
+    //                                  for the current compilation, compatible with available
+    //                                  InstructionSet flags.
+    //
     // Note - cannot be used for System.Runtime.Intrinsic
-    uint32_t getVectorTByteLength()
+    //
+    // Returns:
+    //   The size in bytes of Vector<T>.
+    //   Arm64: This function may return the sentinel value SIZE_UNKNOWN to indicate that the
+    //          size of Vector<T> is not known at compile time. A compilation in JIT mode may
+    //          call getRuntimeVectorTByteLength to determine the actual size instead.
+    //
+    uint32_t getCompileTimeVectorTByteLength()
     {
         // We need to report the ISA dependency to the VM so that scenarios
         // such as R2R work correctly for larger vector sizes, so we always
@@ -10284,11 +10297,34 @@ class Compiler
         // TODO-WASM: Verify if we need a more complicated condition here
         return FP_REGSIZE_BYTES;
 #else
-        assert(!"getVectorTByteLength() unimplemented on target arch");
+        assert(!"getCompileTimeVectorTByteLength() unimplemented on target arch");
         unreached();
 #endif
     }
 
+    //-------------------------------------------------------------------------------------
+    // getRuntimeVectorTByteLength: Get the size of Vector<T> that will be used at runtime
+    //
+    // Returns:
+    //   The size of Vector<T> as resolved in EE metadata.
+    //
+    uint32_t getRuntimeVectorTByteLength()
+    {
+        uint32_t compileTimeLength = getCompileTimeVectorTByteLength();
+
+        if (compileTimeLength == SIZE_UNKNOWN)
+        {
+            assert(!IsAot());
+            CORINFO_CLASS_HANDLE vectorT = info.compCompHnd->getBuiltinClass(CLASSID_NUMERICS_VECTORT);
+            assert(vectorT != NULL);
+            uint32_t size = info.compCompHnd->getClassSize(vectorT);
+            assert(size > 0);
+            return size;
+        }
+
+        return compileTimeLength;
+    }
+
     // The minimum and maximum possible number of bytes in a SIMD vector.
 
     // getMaxVectorByteLength

src/coreclr/jit/gentree.cpp

@@ -31921,11 +31921,11 @@ ClassLayout* GenTreeHWIntrinsic::GetLayout(Compiler* compiler) const
             return compiler->typGetBlkLayout(64);
 
         case NI_Sve_Load2xVectorAndUnzip:
-            return compiler->typGetBlkLayout(compiler->getVectorTByteLength() * 2);
+            return compiler->typGetBlkLayout(compiler->getRuntimeVectorTByteLength() * 2);
         case NI_Sve_Load3xVectorAndUnzip:
-            return compiler->typGetBlkLayout(compiler->getVectorTByteLength() * 3);
+            return compiler->typGetBlkLayout(compiler->getRuntimeVectorTByteLength() * 3);
         case NI_Sve_Load4xVectorAndUnzip:
-            return compiler->typGetBlkLayout(compiler->getVectorTByteLength() * 4);
+            return compiler->typGetBlkLayout(compiler->getRuntimeVectorTByteLength() * 4);
 
 #endif // TARGET_ARM64
 

src/coreclr/jit/hwintrinsic.cpp

@@ -3208,7 +3208,7 @@ GenTree* Compiler::impXplatIntrinsic(NamedIntrinsic        intrinsic,
         case NI_Vector_AsVector512:
         {
             assert(sig->numArgs == 1);
-            uint32_t vectorTByteLength = getVectorTByteLength();
+            uint32_t vectorTByteLength = getCompileTimeVectorTByteLength();
 
             if (vectorTByteLength == 0)
             {

src/coreclr/jit/importercalls.cpp

@@ -3310,11 +3310,9 @@ GenTree* Compiler::impIntrinsic(CORINFO_CLASS_HANDLE    clsHnd,
                 {
                     CORINFO_CLASS_HANDLE typeArgHnd;
                     CorInfoType          simdBaseJitType;
-                    unsigned             simdSize;
 
                     typeArgHnd      = info.compCompHnd->getTypeInstantiationArgument(clsHnd, 0);
                     simdBaseJitType = info.compCompHnd->getTypeForPrimitiveNumericClass(typeArgHnd);
-                    simdSize        = info.compCompHnd->getClassSize(clsHnd);
 
                     switch (simdBaseJitType)
                     {
@@ -3331,15 +3329,7 @@ GenTree* Compiler::impIntrinsic(CORINFO_CLASS_HANDLE    clsHnd,
                         case CORINFO_TYPE_NATIVEINT:
                         case CORINFO_TYPE_NATIVEUINT:
                         {
-                            var_types      simdBaseType = JitType2PreciseVarType(simdBaseJitType);
-                            unsigned       elementSize  = genTypeSize(simdBaseType);
-                            GenTreeIntCon* countNode    = gtNewIconNode(simdSize / elementSize, TYP_INT);
-
-#if defined(FEATURE_SIMD)
-                            countNode->gtFlags |= GTF_ICON_SIMD_COUNT;
-#endif // FEATURE_SIMD
-
-                            return countNode;
+                            return evalVectorCount(clsHnd, JitType2PreciseVarType(simdBaseJitType));
                         }
 
                         default:
@@ -11368,7 +11358,7 @@ NamedIntrinsic Compiler::lookupNamedIntrinsic(CORINFO_METHOD_HANDLE method)
                                 }
                             }
 
-                            uint32_t size = getVectorTByteLength();
+                            uint32_t size = getCompileTimeVectorTByteLength();
 #ifdef TARGET_ARM64
                             assert((size == 16) || (size == SIZE_UNKNOWN));
 #else
@@ -12512,6 +12502,31 @@ GenTree* Compiler::impUnsupportedNamedIntrinsic(unsigned              helper,
     }
 }
 
+//-------------------------------------------------------------------------
+// evalVectorCount: Evaluate the Count property of a vector intrinsic class using
+//                  EE metadata.
+//
+// Arguments:
+//     vectorHandle -- handle to the vector class to query for size
+//     simdBaseType -- base type, whose size to use as the divisor
+//
+// Returns:
+//     The number of elements in the vector with this base type, expressed as a constant
+//     signed integer IR node.
+GenTree* Compiler::evalVectorCount(CORINFO_CLASS_HANDLE vectorHandle, var_types simdBaseType)
+{
+    unsigned simdSize = info.compCompHnd->getClassSize(vectorHandle);
+
+    unsigned       elementSize = genTypeSize(simdBaseType);
+    GenTreeIntCon* countNode   = gtNewIconNode(simdSize / elementSize, TYP_INT);
+
+#if defined(FEATURE_SIMD)
+    countNode->gtFlags |= GTF_ICON_SIMD_COUNT;
+#endif // FEATURE_SIMD
+
+    return countNode;
+}
+
 //------------------------------------------------------------------------
 // impArrayAccessIntrinsic: try to replace a multi-dimensional array intrinsics with IR nodes.
 //

src/coreclr/jit/simd.cpp

@@ -308,13 +308,12 @@ var_types Compiler::getBaseTypeAndSizeOfSIMDType(CORINFO_CLASS_HANDLE typeHnd, u
                         }
 
                         JITDUMP(" Found Vector<%s>\n", varTypeName(simdBaseType));
-                        size = getVectorTByteLength();
+                        size = getCompileTimeVectorTByteLength();
 
                         if (size == 0)
                         {
                             return TYP_UNDEF;
                         }
-
                         // Vector<T>'s length is target-dependent, so under a cross-targeting altjit (e.g.
                         // SuperPMI replaying a context captured for a target with a different Vector<T>
                         // length) our size can disagree with the VM's. Treat it as a regular struct then,

src/coreclr/vm/jitinterface.cpp

@@ -4048,6 +4048,9 @@ CORINFO_CLASS_HANDLE CEEInfo::getBuiltinClass(CorInfoClassId classId)
     case CLASSID_RUNTIME_TYPE:
         result = CORINFO_CLASS_HANDLE(g_pRuntimeTypeClass);
         break;
+    case CLASSID_NUMERICS_VECTORT:
+        result = CORINFO_CLASS_HANDLE(CoreLibBinder::GetClass(CLASS__VECTORT));
+        break;
     default:
         _ASSERTE(!"NYI: unknown classId");
         break;