[X86][AMX][NFC] Avoid assert for the same immidiate value

[pengfei]

Summary

The previous condition in the assert was over strict. We ought to allow
the same immidiate value being loaded more than once. The intention for
the assert is to check the same AMX register uses multiple different
immidiate shapes. So this fix supposes to be NFC.

[LuoYuanke]

LGTM.

llvm/lib/Target/X86/X86TileConfig.cpp

for (auto &R : {Shape.getRow()->getReg(), Shape.getCol()->getReg()}) {
       // 30-31  tile7.colsb Tile 7 bytes per row.
       // 32-47  reserved, must be zero
       // 48     tile0.rows Tile 0 rows.
       // 49     tile1.rows Tile 1 rows.
       // 50     tile2.rows Tile 2 rows.
       // ... (sequence continues)
       // 55     tile7.rows Tile 7 rows.
       // 56-63  reserved, must be zero
-      int ImmCount = 0;
-      (void)ImmCount;
+      int64_t Imm = INT64_MAX;
       int Offset = IsRow ? 48 + I : 16 + I * 2;
       for (auto &DefMI : MRI.def_instructions(R)) {
         MachineBasicBlock &MBB = *DefMI.getParent();
         if (DefMI.isMoveImmediate()) {
+          if (Imm != INT64_MAX) {
             // FIXME: We should handle this case in future.
-          assert(++ImmCount == 1 && "Cannot initialize with different shapes");
+            assert(Imm == DefMI.getOperand(1).getImm() &&
+                   "Cannot initialize with different shapes");
+            continue;
+          }
+          Imm = DefMI.getOperand(1).getImm();
           NewMI = addFrameReference(
                       BuildMI(MF.front(), ++ConstMI->getIterator(), DL,
                               TII->get(IsRow ? X86::MOV8mi : X86::MOV16mi)),
                       SS, Offset)
-                      .addImm(DefMI.getOperand(1).getImm());
+                      .addImm(Imm);
           ConstMI = NewMI;
           LIS.InsertMachineInstrInMaps(*NewMI);
         } else {
           unsigned SubIdx = IsRow ? X86::sub_8bit : X86::sub_16bit;
           unsigned RegSize = TRI->getRegSizeInBits(*MRI.getRegClass(R));
           if ((IsRow && RegSize == 8) || (!IsRow && RegSize == 16))
             SubIdx = 0;
           auto Iter = DefMI.getIterator();