Clean up

Author: EgorBo

src/coreclr/jit/emitarm64.cpp

@@ -13483,24 +13483,13 @@ void emitter::emitInsLoadStoreOp(instruction ins, emitAttr attr, regNumber dataR
                 {
                     if (index->OperIs(GT_BFIZ) && index->isContained())
                     {
+                        // Then load/store dataReg from/to [memBase + index*scale with sign/zero extension]
                         GenTreeCast* cast = index->gtGetOp1()->AsCast();
-                        assert(cast->isContained());
+                        assert(cast->isContained() && varTypeToSigned(cast->CastFromType()) == TYP_INT);
                         const bool isZeroExtended = cast->IsUnsigned() || varTypeIsUnsigned(cast->CastToType());
-                        insOpts    opts           = INS_OPTS_NONE;
-                        int        shift          = (int)index->gtGetOp2()->AsIntCon()->IconValue();
-                        switch (shift)
-                        {
-                            case 2:
-                                opts = isZeroExtended ? INS_OPTS_UXTW : INS_OPTS_SXTW;
-                                break;
-                            case 3:
-                                opts = isZeroExtended ? INS_OPTS_UXTX : INS_OPTS_SXTX;
-                                break;
-                            default:
-                                unreached();
-                        }
-                        emitIns_R_R_R_Ext(ins, attr, dataReg, memBase->GetRegNum(), cast->CastOp()->GetRegNum(), opts,
-                                          shift);
+                        emitIns_R_R_R_Ext(ins, attr, dataReg, memBase->GetRegNum(), cast->CastOp()->GetRegNum(),
+                                          isZeroExtended ? INS_OPTS_UXTW : INS_OPTS_SXTW,
+                                          (int)index->gtGetOp2()->AsIntCon()->IconValue());
                     }
                     else
                     {

src/coreclr/jit/lower.cpp

@@ -5046,7 +5046,8 @@ bool Lowering::TryCreateAddrMode(GenTree* addr, bool isContainable, var_types ta
         unsigned castFrom = genTypeSize(cast->CastFromType());
         unsigned target   = genTypeSize(targetType);
 
-        // For now only two the most popular cases are handled. TODO: extend
+        // For now we only handle the most popular case for indices 32 -> 64 sign/zero extension
+        // Where target is 32 or 64. TODO: enable for 8 and 16
         if ((castFrom == 4) && (castTo == 8) && (target == (1U << shiftBy)) && (target >= 4) && (scale == 1) &&
             (offset == 0))
         {