[js/webgpu] workaround the matmul vec4 issue

This PR uses `indicesToOffset` instead of `get[set]ByIndices`  to
read/write data from buffer in matmul due to matmul vec4 can't get
correct result when the shape size is large(testsed in mobilenetv2).
It seems like an intel driver bug for fxc support. It works well when
switching to dxc even without this PR.

js/web/lib/wasm/jsep/webgpu/ops/3rd-party/matmul_packed_webgpu.ts

@@ -358,7 +358,7 @@ const matMulReadWriteFnSource =
           resStr += `\naIndices[${i}] = 0;`;
         });
         resStr += `\naIndices[${aRank - 2}] = u32(row);
-                   aIndices[${aRank - 1}] = u32(colIn);`;
+                   aIndices[${aRank - 1}] = u32(col);`;
         return resStr;
       };
       const getBIndices = () => {
@@ -372,7 +372,7 @@ const matMulReadWriteFnSource =
           resStr += `\nbIndices[${i}] = 0;`;
         });
         resStr += `\nbIndices[${bRank - 2}] = u32(row);
-                   bIndices[${bRank - 1}] = u32(colIn);`;
+                   bIndices[${bRank - 1}] = u32(col);`;
         return resStr;
       };
       const source = `
@@ -383,7 +383,8 @@ const matMulReadWriteFnSource =
       if(row < dimAOuter && col < dimInner)
       {
         ${getAIndices()}
-        value = ${aVariable.getByIndices('aIndices')};
+        // TODO: recover to use getByIndices/setByIndices when dxc is supported.
+        value = a[${aVariable.indicesToOffset('aIndices')}${component === 1 ? '' : `/ ${component}`}];
       }
       return value;
     }
@@ -395,7 +396,7 @@ const matMulReadWriteFnSource =
       if(row < dimInner && col < dimBOuter)
       {
         ${getBIndices()}
-        value = ${bVariable.getByIndices('bIndices')};
+        value = b[${bVariable.indicesToOffset('bIndices')}${component === 1 ? '' : `/ ${component}`}];
       }
       return value;
     }
@@ -404,10 +405,11 @@ const matMulReadWriteFnSource =
       let col = colIn * ${component};
       if (row < dimAOuter && col < dimBOuter) {
         var value = valueIn;
-        let coords = vec3<i32>(batch, row, colIn);
+        let coords = vec3<i32>(batch, row, col);
         ${hasBias ? 'value = value + bias[colIn];' : ''}
         ${applyActivation}
-        ${outputVariable.setByIndices('vec3<u32>(coords)', 'value')}
+        result[${outputVariable.indicesToOffset('vec3<u32>(coords)')}${
+          component === 1 ? '' : `/ ${component}`}] = value;
       }
     }
     `;
@@ -446,18 +448,17 @@ export const createMatmulProgramInfo =
       ];
 
       const components = isVec4 ? 4 : 1;
-      const A = inputVariable('a', inputs[0].dataType, [...outerDimsA, dimAOuter, dimInner / components], components);
-      const B = inputVariable('b', inputs[1].dataType, [...outerDimsB, dimInner, dimBOuter / components], components);
-      const output =
-          outputVariable('result', inputs[0].dataType, [batchSize, dimAOuter, dimBOuter / components], components);
+      const A = inputVariable('a', inputs[0].dataType, [...outerDimsA, dimAOuter, dimInner], components);
+      const B = inputVariable('b', inputs[1].dataType, [...outerDimsB, dimInner, dimBOuter], components);
+      const output = outputVariable('result', inputs[0].dataType, [batchSize, dimAOuter, dimBOuter], components);
       variables.push(A);
       variables.push(B);
       variables.push(output);
       const inputVariables = [A, B];
       const hasBias = inputs.length > 2;
       const declareFunctions = matMulReadWriteFnSource(component, hasBias, applyActivation, variables);
       if (hasBias) {
-        inputVariables.push(inputVariable('bias', inputs[2].dataType, [dimBOuter / components], components));
+        inputVariables.push(inputVariable('bias', inputs[2].dataType, [dimBOuter], components));
       }
       const getShaderSource = (shaderHelper: ShaderHelper) => `
   const dimAOuter: i32 = ${dimAOuter};