replaceSymbolicSizes needs to process the first appearing ID in the same way as the rest of the IDs

[naoyam]

Noticed some strange replacement result while working on #3344. Repro:

  auto tv0 = makeSymbolicTensor(3);
  fusion.addInput(tv0);
  auto tv1 = makeSymbolicTensor(2);
  fusion.addInput(tv1);
  auto i0 = IrBuilder::create<Val>(DataType::Index);
  fusion.addInput(i0);

  auto tv2 = reshape(tv0, {i0});
  auto tv3 = reshape(tv1, {i0});
  auto tv4 = add(tv2, tv3);
  fusion.addOutput(tv4);

  ExpressionEvaluator expr_eval;

  expr_eval.bind(tv0->axis(0)->extent(), 2L);
  expr_eval.bind(tv0->axis(1)->extent(), 4L);
  expr_eval.bind(tv0->axis(2)->extent(), 8L);
  expr_eval.bind(tv1->axis(0)->extent(), 8L);
  expr_eval.bind(tv1->axis(1)->extent(), 8L);
  expr_eval.bind(i0, 64L);

  auto initial_info = DynamicTransform::getInitialInfo(&fusion);
  auto info = DynamicTransformConcretizationInfo(&initial_info, &expr_eval);

  DynamicTransform::concretizeFusion(&fusion, &info);

  replaceSymbolicSizes(&fusion);

Before replacement:

Inputs:
  T0_g_float[ iS0{i0}, iS1{i2}, iS2{i3} ]
  T1_g_float[ iS3{i4}, iS4{i5} ]
  i6
Outputs:
  T4_g_float[ iS26{i6} ]

%kernel_math {
T5_l_float[ iS20{( ( i0 * i2 ) * i3 )}rf ] = view( T0_g_float[ iS0{i0}, iS1{i2}, iS2{i3} ] )
T6_l_float[ iS25{( i4 * i5 )}rf ] = view( T1_g_float[ iS3{i4}, iS4{i5} ] )
T4_g_float[ iS26{i6} ]
   = T5_l_float[ iS20{( ( i0 * i2 ) * i3 )}rf ]
   + T6_l_float[ iS25{( i4 * i5 )}rf ];
} // %kernel_math

After replacement:

Inputs:
  T0_g_float[ iS33{( (( (( getMetaData(T0) )).logical_size ))[0] )}, iS34{( (( (( getMetaData(T0) )).logical_size ))[1] )}, iS35{( (( (( getMetaData(T0) )).logical_size ))[2] )} ]
  T1_g_float[ iS36{( (( (( getMetaData(T1) )).logical_size ))[0] )}, iS37{( (( (( getMetaData(T1) )).logical_size ))[1] )} ]
  i6
Outputs:
  T4_g_float[ iS26{i6} ]

%kernel_math {
T5_l_float[ iS20{( ( ( (( (( getMetaData(T0) )).logical_size ))[0] ) * ( (( (( getMetaData(T0) )).logical_size ))[1] ) ) * ( (( (( getMetaData(T0) )).logical_size ))[2] ) )}rf ] = view( T0_g_float[ iS33{( (( (( getMetaData(T0) )).logical_size ))[0] )}, iS34{( (( (( getMetaData(T0) )).logical_size ))[1] )}, iS35{( (( (( getMetaData(T0) )).logical_size ))[2] )} ] )
T6_l_float[ iS32{( ( ( (( (( getMetaData(T0) )).logical_size ))[0] ) * ( (( (( getMetaData(T0) )).logical_size ))[1] ) ) * ( (( (( getMetaData(T0) )).logical_size ))[2] ) )}rf ] = view( T1_g_float[ iS36{( (( (( getMetaData(T1) )).logical_size ))[0] )}, iS37{( (( (( getMetaData(T1) )).logical_size ))[1] )} ] )
T4_g_float[ iS26{i6} ]
   = T5_l_float[ iS20{( ( ( (( (( getMetaData(T0) )).logical_size ))[0] ) * ( (( (( getMetaData(T0) )).logical_size ))[1] ) ) * ( (( (( getMetaData(T0) )).logical_size ))[2] ) )}rf ]
   + T6_l_float[ iS32{( ( ( (( (( getMetaData(T0) )).logical_size ))[0] ) * ( (( (( getMetaData(T0) )).logical_size ))[1] ) ) * ( (( (( getMetaData(T0) )).logical_size ))[2] ) )}rf ];
} // %kernel_math

Notice that T4 is still T4_g_float[ iS26{i6} ].

[kevinstephano]

Should this be tagged with a work stream area?
Is this a bug or a task?
Who should this be assigned to?

[naoyam]

I'm working on it #3346. Not strictly related but found a (small) rabbit hole around extent replacements and simplifications while working on slices and concat.

[naoyam]

Fixed by #3346