Add support for conv_transpose2d on Metal backend (#1903)

* add support for conv transpose 2d and add bench mark for float types

* update bench calculation

* enable testing all conv operations on metal

candle-metal-kernels/src/lib.rs

@@ -1970,5 +1970,63 @@ pub fn call_conv_transpose1d(
     Ok(())
 }
 
+pub struct CallConvTranspose2dCfg<'a> {
+    pub dilation: usize,
+    pub stride: usize,
+    pub padding: usize,
+    pub output_padding: usize,
+    pub c_out: usize,
+    pub out_w: usize,
+    pub out_h: usize,
+    pub b_size: usize,
+    pub input_dims: &'a [usize],
+    pub input_stride: &'a [usize],
+    pub kernel_dims: &'a [usize],
+    pub kernel_stride: &'a [usize],
+    pub input_offset: usize,
+    pub kernel_offset: usize,
+}
+
+pub fn call_conv_transpose2d(
+    device: &Device,
+    command_buffer: &CommandBufferRef,
+    kernels: &Kernels,
+    name: &'static str,
+    cfg: CallConvTranspose2dCfg,
+    input: &Buffer,
+    kernel: &Buffer,
+    output: &Buffer,
+) -> Result<(), MetalKernelError> {
+    let dst_el = cfg.c_out * cfg.out_w * cfg.out_h * cfg.b_size;
+    let pipeline: ComputePipelineState = kernels.load_pipeline(device, Source::Conv, name)?;
+    let (thread_group_count, thread_group_size) = linear_split(&pipeline, dst_el);
+    let encoder = command_buffer.new_compute_command_encoder();
+    encoder.set_compute_pipeline_state(&pipeline);
+    set_params!(
+        encoder,
+        (
+            cfg.out_w,
+            cfg.out_h,
+            cfg.stride,
+            cfg.padding,
+            cfg.output_padding,
+            cfg.dilation,
+            cfg.input_dims,
+            cfg.input_stride,
+            cfg.kernel_dims,
+            cfg.kernel_stride,
+            (input, cfg.input_offset),
+            (kernel, cfg.kernel_offset),
+            output
+        )
+    );
+    encoder.use_resource(input, metal::MTLResourceUsage::Read);
+    encoder.use_resource(kernel, metal::MTLResourceUsage::Read);
+    encoder.use_resource(output, metal::MTLResourceUsage::Write);
+    encoder.dispatch_thread_groups(thread_group_count, thread_group_size);
+    encoder.end_encoding();
+    Ok(())
+}
+
 #[cfg(test)]
 mod tests;