[LoongArch64] Fix some bugs in the test sets 'System.Runtime.Tests' a…

…nd 'System.Linq.Expressions.Tests' for loongarch64. (#86435)

* Fix the error of the Truncate/Saturate convert from Float/Double NAN to UINT32/UINT64.
* fix some random failed testcases in System.Runtime.Tests.

* Update codegenloongarch64.cpp

Fix the RangeCheck bug of the TYP_INT case in CodeGen::genRangeCheck().

src/coreclr/jit/codegencommon.cpp

@@ -5827,7 +5827,7 @@ void CodeGen::genFnProlog()
         //
         extraFrameSize = compiler->compCalleeRegsPushed * REGSIZE_BYTES;
     }
-#endif // TARGET_ARM64
+#endif // TARGET_AMD64
 
     if (doubleAlignOrFramePointerUsed())
     {

src/coreclr/jit/codegenloongarch64.cpp

@@ -3877,17 +3877,24 @@ void CodeGen::genFloatToIntCast(GenTree* treeNode)
         }
 
         if (srcType == TYP_DOUBLE)
+        {
             GetEmitter()->emitIns_R_R_I(INS_lu52i_d, EA_8BYTE, REG_R21, REG_R0, imm >> 8);
+        }
         else
+        {
             GetEmitter()->emitIns_R_I(INS_lu12i_w, EA_PTRSIZE, REG_R21, imm);
+        }
 
         GetEmitter()->emitIns_R_R(srcType == TYP_DOUBLE ? INS_movgr2fr_d : INS_movgr2fr_w, EA_8BYTE, tmpReg, REG_R21);
 
         GetEmitter()->emitIns_R_R_I(srcType == TYP_DOUBLE ? INS_fcmp_clt_d : INS_fcmp_clt_s, EA_8BYTE, op1->GetRegNum(),
-                                    tmpReg, 2);
+                                    tmpReg, 2); // cc=2
+
+        GetEmitter()->emitIns_R_R_I(srcType == TYP_DOUBLE ? INS_fcmp_ceq_d : INS_fcmp_ceq_s, EA_8BYTE, op1->GetRegNum(),
+                                    tmpReg, 3); // cc=3
 
         GetEmitter()->emitIns_R_R_I(INS_ori, EA_PTRSIZE, REG_R21, REG_R0, 0);
-        GetEmitter()->emitIns_I_I(INS_bcnez, EA_PTRSIZE, 2, 4 << 2);
+        GetEmitter()->emitIns_I_I(INS_bcnez, EA_PTRSIZE, 2, 4 << 2); // cc=2
 
         GetEmitter()->emitIns_R_R_R(srcType == TYP_DOUBLE ? INS_fsub_d : INS_fsub_s, EA_8BYTE, tmpReg, op1->GetRegNum(),
                                     tmpReg);
@@ -3901,6 +3908,9 @@ void CodeGen::genFloatToIntCast(GenTree* treeNode)
         GetEmitter()->emitIns_R_R(ins1, dstSize, tmpReg, tmpReg);
         GetEmitter()->emitIns_R_R(ins2, dstSize, treeNode->GetRegNum(), tmpReg);
 
+        GetEmitter()->emitIns_I_I(INS_bcnez, EA_PTRSIZE, 3, 2 << 2); // cc=3
+        GetEmitter()->emitIns_R_I(INS_beqz, EA_PTRSIZE, treeNode->GetRegNum(), 2 << 2);
+
         GetEmitter()->emitIns_R_R_R(INS_or, dstSize, treeNode->GetRegNum(), REG_R21, treeNode->GetRegNum());
     }
     else
@@ -4104,20 +4114,22 @@ void CodeGen::genCodeForCompare(GenTreeOp* tree)
             switch (cmpSize)
             {
                 case EA_4BYTE:
+                {
+                    regNumber tmpRegOp1 = REG_R21;
+                    assert(regOp1 != tmpRegOp1);
                     if (IsUnsigned)
                     {
                         imm = static_cast<uint32_t>(imm);
-
-                        regNumber tmpRegOp1 = REG_R21;
-                        assert(regOp1 != tmpRegOp1);
                         emit->emitIns_R_R_I_I(INS_bstrpick_d, EA_8BYTE, tmpRegOp1, regOp1, 31, 0);
-                        regOp1 = tmpRegOp1;
                     }
                     else
                     {
                         imm = static_cast<int32_t>(imm);
+                        emit->emitIns_R_R_I(INS_slli_w, EA_8BYTE, tmpRegOp1, regOp1, 0);
                     }
+                    regOp1 = tmpRegOp1;
                     break;
+                }
                 case EA_8BYTE:
                     break;
                 case EA_1BYTE:
@@ -5932,6 +5944,11 @@ void CodeGen::genRangeCheck(GenTree* oper)
         }
         else
         {
+            if (genActualType(src1->TypeGet()) == TYP_INT)
+            {
+                GetEmitter()->emitIns_R_R_I(INS_slli_w, EA_4BYTE, REG_R21, reg1, 0);
+                reg1 = REG_R21;
+            }
             reg2 = src2->GetRegNum();
         }
     }