diff --git a/index.bs b/index.bs
index f6fafdc0..96cd6729 100644
--- a/index.bs
+++ b/index.bs
@@ -1054,7 +1054,7 @@ The {{MLActivation}} objects (including the ones passed as input to methods) are
 
 <details open>
   <summary>
-    To <dfn>create MLActivation</dfn> given |builder|, |name| and |options|, run the following steps:
+    To <dfn>create MLActivation</dfn> given |builder|, |name|, |options| and |init-steps|, run the following steps:
   </summary>
   <div class=algorithm-steps>
     1. If |builder| is not an instance of {{MLGraphBuilder}}, throw a "{{TypeError}}" and abort these steps.
@@ -1063,8 +1063,12 @@ The {{MLActivation}} objects (including the ones passed as input to methods) are
     1. Set |activation|.{{MLActivation/[[builder]]}} to |builder|.
     1. Set |activation|.{{MLActivation/[[name]]}} to |name|.
     1. If |options| is an [=object=], set |activation|.{{MLActivation/[[options]]}} to |options|.
-    1. Make a request to the underlying platform to bind the [=implementation-defined=] platform operator for |name| to |activation|.{{MLActivation/[[operator]]}}.
-        1. If that fails, throw a "{{TypeError}}" and abort these steps.
+    1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
+        1. Make a request to the underlying platform to:
+            1. Create an [=implementation-defined=] platform operator |opImpl| for the given |name| operation.
+            1. Store a reference of |opImpl| in |activation|.{{MLActivation/[[operator]]}}.
+        1. If |init-steps| are defined, run |init-steps| with |options|.
+            1. Otherwise, initialize |activation|.{{MLActivation/[[operator]]}} given |options| in an [=implementation-defined=] way for the given |name| operation.
     1. Return |activation|.
   </div>
 </details>
@@ -1580,11 +1584,13 @@ Create a named {{MLOperand}} based on a descriptor, that can be used as an input
         1. If |descriptor|.{{MLOperandDescriptor/dimensions}} [=map/exists=]:
             1. If the [=check dimensions=] steps given |descriptor|.{{MLOperandDescriptor/type}} and |descriptor|.{{MLOperandDescriptor/dimensions}} return `false`, throw a "{{DataError}}" {{DOMException}} and stop.
             1. If the [=byte length=] of |descriptor| is not supported by the underlying platform, then throw a "{{DataError}}" {{DOMException}} and stop.
-    1. Let |operand| be the result of invoking the <a>create MLOperand</a> steps with [=this=] and |descriptor|.
-        1. If that throws, re-throw the exception and stop.
-    1. Set |operand|.{{MLOperand/[[name]]}} to |name|.
-    1. Make a request to the underlying platform to register |operand| as an input and store a reference to the corresponding [=implementation-defined=] platform object in |operand|.{{MLOperand/[[operand]]}}.
-        1. If that fails, throw an "{{OperationError}}" {{DOMException}} and abort these steps.
+    1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
+        1. Let |operand| be the result of invoking the <a>create MLOperand</a> steps with [=this=] and |descriptor|.
+        1. Set |operand|.{{MLOperand/[[name]]}} to |name|.
+        1. Make a request to the underlying platform to:
+            1. Create an [=implementation-defined=] platform input operand |operandImpl| given |descriptor|.
+            1. Store a reference of |operandImpl| in |operand|.{{MLOperand/[[operand]]}}.
+            1. Register |operand| as an input.
     1. Return |operand|.
   </div>
 </details>
@@ -1614,11 +1620,13 @@ Create a constant {{MLOperand}} that can be used in {{MLGraphBuilder}} methods.
         1. If the [=check dimensions=] steps given |descriptor|.{{MLOperandDescriptor/type}} and |descriptor|.{{MLOperandDescriptor/dimensions}} return `false`, throw a "{{DataError}}" {{DOMException}} and stop.
     1. Let |bufferView| be the second argument.
         1. If invoking <a>validate buffer with descriptor</a> given |bufferView| and |descriptor| return `false`, then throw a "{{TypeError}}" {{DOMException}} and stop.
-    1. Let |operand| be the result of invoking the <a>create MLOperand</a> steps with [=this=] and |descriptor|.
-        1. If that throws, re-throw the exception and stop.
-    1. Let |bytes| be the result of invoking [[=get a copy of the bytes held by the buffer source=]] given |bufferView|.
-    1. Make a request to the underlying platform to register |operand| as a tensor constant with |bytes| as value and store a reference to the corresponding [=implementation-defined=] object to |operand|.{{MLOperand/[[operand]]}}.
-        1. If that fails, throw an "{{OperationError}}" {{DOMException}} and stop.
+    1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
+        1. Let |operand| be the result of invoking the <a>create MLOperand</a> steps with [=this=] and |descriptor|.
+        1. Let |bytes| be the result of invoking [[=get a copy of the bytes held by the buffer source=]] given |bufferView|.
+        1. Make a request to the underlying platform to:
+            1. Create an [=implementation-defined=] platform operand |constantImpl| to represent a constant, given |descriptor|.
+            1. Store a reference of |constantImpl| in |operand|.{{MLOperand/[[operand]]}}.
+            1. Register |operand| as a tensor constant with |bytes| as value.
     1. Return |operand|.
   </div>
 </details>
@@ -1649,10 +1657,12 @@ Create a constant {{MLOperand}} that can be used in {{MLGraphBuilder}} methods.
             <div class="note">
                 In the case of a scalar constant, |descriptor|.{{MLOperandDescriptor/dimensions}} is ignored.
             </div>
-    1. Let |operand| be the result of invoking the <a>create MLOperand</a> steps with [=this=] and |descriptor|.
-        1. If that throws, re-throw the exception and stop.
-    1. Make a request to the underlying platform to register |operand| as a scalar constant with |value| as value and store a reference of the [=implementation-defined=] platform object for the corresponding (scalar or tensor constant) operand to |operand|.{{MLOperand/[[operand]]}}.
-        1. If that throws, re-throw the error and stop.
+    1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
+        1. Let |operand| be the result of invoking the <a>create MLOperand</a> steps with [=this=] and |descriptor|.
+        1. Make a request to the underlying platform to:
+            1. Create an [=implementation-defined=] platform operand |constantImpl| to represent a constant, given |descriptor|.
+            1. Store a reference of |constantImpl| in |operand|.{{MLOperand/[[operand]]}}.
+            1. Register |operand| as a scalar constant with |value| as value.
     1. Return |operand|.
   </div>
 </details>
@@ -1724,12 +1734,13 @@ partial interface MLGraphBuilder {
         1. If |options|.axis is not a number between 0 and the rank of |input|, then throw a "{{TypeError}}" {{DOMException}} and abort these steps.
         1. If |input| is a 4-D tensor of the *"nchw"* layout, set |options|.axis to 1.
         1. If |input| is a 4-D tensor of the *"nhwc"* layout, set |options|.axis to 3.
-    1. Let |result| be an {{MLOperand}} representing the results. It may use the same underlying data as |input|.
-    1. Issue a request to the underlying platform to initialize the batch normalization, passing the arguments |input|, |mean|, |variance| and |options| and given |result| to store the results and |options|. Wait for completion.
-        <div class="informalsteps">
-            1. If |options|.activation [=map/exists=], implementations MAY use it to optimize the operation flow.
-        </div>
-    1. Return |result|.
+    1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
+        1. Let |output| be the result of invoking the <a>create MLOperand</a> steps with [=this=] and |descriptor|, that may use the same underlying data as |input|.
+        1. Make a request to the underlying platform to initialize the batch normalization:
+            1. Create an [=implementation-defined=] platform operator |batchNormImpl| for this method, given |input|, |mean|, |variance| and |options|.
+            1. If |options|.activation [=map/exists=],register it as activation to |batchNormImpl|.
+            1. Connect |output| as output to |batchNormImpl|.
+    1. Return |output|.
   </div>
 </details>
 
@@ -1824,16 +1835,16 @@ partial interface MLGraphBuilder {
     1. Let |operand| be the first argument.
     1. Let |options| be the second argument.
         1. If running the <a>check clamp options</a> steps with |options| returns `false`, then throw a "{{TypeError}}" {{DOMException}} and abort these steps.
-    1. Let |result| be the result of invoking the <a>copy MLOperand</a> steps given |operand|.
-            1. If that throws an error, re-throw the error and abort these steps.
     1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
-        1. Make a request to the underlying platform to create an [=implementation-defined=] platform operand |operandImpl| given |result|.{{MLOperand/[[descriptor]]}}.
-        1. Store a reference to |operandImpl| in |result|.{{MLOperand/[[operand]]}}.
-        1. Make a request to the underlying platform to create an [=implementation-defined=] platform operator |operatorImpl| for clamp with |options|.{{MLClampOptions/minValue}} and |options|.{{MLClampOptions/minValue}}.
-        1. Register the |operand|.{{MLOperand/[[operand]]}} as an input to |operatorImpl|.
-        1. Register the |result|.{{MLOperand/[[operand]]}} as output to |operatorImpl|.
-        1. Store a reference to |operatorImpl| in |result|.{{MLOperand/[[operator]]}}.
-    1. Return |result|.
+        1. Let |output| be the result of invoking the <a>copy MLOperand</a> steps given |operand|.
+        1. Make a request to the underlying platform to:
+            1. Create an [=implementation-defined=] platform operator |clampImpl| for this method, given |options|.{{MLClampOptions/minValue}} and |options|.{{MLClampOptions/minValue}}.
+            1. Store a reference of |clampImpl| in |output|.{{MLOperand/[[operator]]}}.
+            1. Create an [=implementation-defined=] platform operand |outputImpl| to represent clamp output, given |output| and |clampImpl|.
+            1. Store a reference to |outputImpl| in |output|.{{MLOperand/[[operand]]}}.
+        1. Connect |operand|.{{MLOperand/[[operand]]}} as input to |clampImpl|.
+        1. Connect |output|.{{MLOperand/[[operand]]}} as output to |clampImpl|.
+    1. Return |output|.
   </div>
 </details>
 
@@ -1856,9 +1867,6 @@ partial interface MLGraphBuilder {
         1. If running the <a>check clamp options</a> steps with |options| returns `false`, then throw a "{{TypeError}}" {{DOMException}} and abort these steps.
     1. Let |op| be the result of invoking the <a>create MLActivation</a> steps with `"clamp"` and |options|.
         1. If that throws an error, re-throw the error and abort these steps.
-    1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
-        1. Make a request to the underlying platform to connect |op| with the [=implementation-defined=] platform operator for clamp |operatorImpl|.
-        1. Store a reference to |operatorImpl| in |op|.{{MLActivation/[[operator]]}}.
     1. Return |op|.
   </div>
 </details>
@@ -1910,10 +1918,15 @@ partial interface MLGraphBuilder {
                     1. If |dim| is not equal to |axis| and if |inputs|[|index|].{{MLOperandDescriptor/dimensions}}[|dim|] is not equal to |inputs|[0].{{MLOperandDescriptor/dimensions}}[|dim|], fail.
                     1. If |inputs|[|dim|].{{MLOperandDescriptor/type}} is not equal to |inputs|[0].{{MLOperandDescriptor/type}}.
                     1. If |dim| is equal to |axis|, add to |desc|.{{MLOperandDescriptor/dimensions}}[|axis|] the value of |inputs|[|index|].{{MLOperandDescriptor/dimensions}}[|dim|].
-        1. Let |output| be the result of invoking the <a>create MLOperand</a> steps given [=this=] and |desc|.
-            1. If that throws an error, re-throw the error and stop.
-        1. Make a request to the underlying platform to create an operator for this method with |inputs| connected as input and |output| connected as output and store a reference to the [=implementation-defined=] platform object to |output|.{{MLOperand/[[operand]]}}.
-            1. If that fails, throw a "{{DataError}}" {{DOMException}} and stop.
+        1. If any of the following sub-steps fail, throw an "{{OperationError}}" {{DOMException}} and stop.
+            1. Let |output| be the result of invoking the <a>create MLOperand</a> steps given [=this=] and |desc|.
+            1. Make a request to the underlying platform to:
+                1. Create an [=implementation-defined=] platform operator |concatImpl| for this method, given |inputs| and |axis|.
+                1. Store a reference of |concatImpl| in |output|.{{MLOperand/[[operator]]}}.
+                1. Create an [=implementation-defined=] platform operand |outputImpl| to represent output,given |output| and |concatImpl|.
+                1. Store a reference to |outputImpl| in |output|.{{MLOperand/[[operand]]}}.
+            1. Connect |inputs| as input to |concatImpl|.
+            1. Connect |output|.{{MLOperand/[[operand]]}} as output to |concatImpl|.
         1. Return |output|.
   </div>
 </details>
@@ -2712,7 +2725,7 @@ partial interface MLGraphBuilder {
         - *options*: an optional {{MLGruOptions}}. The optional parameters of the operation.
             - *bias*: an {{MLOperand}}. The 2-D input bias tensor of shape [num_directions, 4 * hidden_size]. The ordering of the bias vectors in the second dimension of the tensor shape is specified according to the *options.layout* argument.
             - *recurrentBias*: an {{MLOperand}}. The 2-D recurrent bias tensor of shape [num_directions, 4 * hidden_size]. The ordering of the bias vectors in the second dimension of the tensor shape is specified according to the *options.layout* argument.
-            - *peepholeWeight*: an {{MLOperand}}. The 2-D weight tensor for peepholes of shape [num_directions, 4 * hidden_size]. The pack ordering of the weight vectors is for the *input (i)*, *output (o)*, and *forget (f)* gate respectively.
+            - *peepholeWeight*: an {{MLOperand}}. The 2-D weight tensor for peepholes of shape [num_directions, 3 * hidden_size]. The pack ordering of the weight vectors is for the *input (i)*, *output (o)*, and *forget (f)* gate respectively.
             - *initialHiddenState*: an {{MLOperand}}. The 3-D initial hidden state tensor of shape [num_directions, batch_size, hidden_size]. When not specified, it's assumed to be a tensor filled with zero.
             - *initialCellState*: an {{MLOperand}}. The 3-D initial hidden state tensor of shape [num_directions, batch_size, hidden_size]. When not specified, it's assumed to be a tensor filled with zero.
             - *returnSequence*: a {{boolean}} indicating whether to also return the entire sequence with every output from each time step in it in addition to the output of the last time step. Default to false.
@@ -2755,7 +2768,7 @@ partial interface MLGraphBuilder {
       currentRecurrentBias.push(options.recurrentBias ?
         (builder.squeeze(builder.slice(options.recurrentBias, [dir, 0], [1, 4 * hidden_size]), { axes: [0] })) : null);
       currentPeepholeWeight.push(options.peepholeWeight ?
-        (builder.squeeze(builder.slice(options.peepholeWeight, [dir, 0], [1, 4 * hidden_size]), { axes: [0] })) : null);
+        (builder.squeeze(builder.slice(options.peepholeWeight, [dir, 0], [1, 3 * hidden_size]), { axes: [0] })) : null);
     }
 
     for (let step = 0; step < steps; ++step) {
@@ -2782,8 +2795,8 @@ partial interface MLGraphBuilder {
         let output = builder.reshape(results[0], [1, null, hiddenSize]);
         let cell = builder.reshape(results[1], [1, null, hiddenSize]);
 
-        nextHidden = (nextHidden ? builder.concat([nextHidden, result], 0) : output);
-        nextCell = (nextCell ? builder.concat([nextCell, result], 0) : cell);
+        nextHidden = (nextHidden ? builder.concat([nextHidden, output], 0) : output);
+        nextCell = (nextCell ? builder.concat([nextCell, cell], 0) : cell);
       }
 
       hiddenState = nextHidden;