Optimize CpuGemmConv2d start-up time

When weight has no holes, we can replace CpuWeightsReshapeKernel with:
 - Collapse by reinterpreting weight's 3 spatial dimensions
 - Perform CpuTranspose

For more details see the documentation in
src/cpu/operators/CpuGemmConv2d.cpp

This is one optimization since the CpuTranspose is better performing
than CpuWeightsReshapeKernel

A second optimization is to fuse this transpose with other weight
transformations (e.g. pretranspose_B_array in CpuGemmAssemblyDispatch)

However this second optimization depends on how the underlying gemm
methods (the fall back path: CpuGemmMatrixMultiplyKernel or the assembly
path: CpuGemmAssemblyDispatch) chooses to fuse the transpose.

Therefore, this patch moves the transpose down from CpuGemmConv2d, to
the individual gemm operators where the fusion decision needs to be
made, by passing an extra "transpose_b" flag to CpuGemm

New transpose_b flag in different scopes (they are all the same, but
with different names because pretranspose_b has a different meaning in
GemmAssemblyDispatch):
GEMMInfo::pretranspose_B -> AsmGemmInfo::transpose_b

New auxilliary tensors holding the transposed b result:
- CpuGemm optimized path: CpuGemmAssemblyDispatch::PrePretransposedB
- CpuGemm fallback path:  CpuGemm::PreTransposedRHS

Note that this patch does not yet have the second optimization
(COMPMID-6595), but it prepares for it.

Relates to COMPMID-6595
Resolves COMPMID-6499

Change-Id: I999a2da9da4b2b15369a3cc06d7872c86e0190ea
Signed-off-by: SiCong Li <sicong.li@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/10526
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Anitha Raj <Anitha.Raj@arm.com>
Reviewed-by: Gunes Bayir <gunes.bayir@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Benchmark: Arm Jenkins <bsgcomp@arm.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/arm_compute/runtime/NEON/functions/NEConvolutionLayer.h b/arm_compute/runtime/NEON/functions/NEConvolutionLayer.h
index cdf0f652e1..2d07980ade 100644
--- a/arm_compute/runtime/NEON/functions/NEConvolutionLayer.h
+++ b/arm_compute/runtime/NEON/functions/NEConvolutionLayer.h
@@ -21,8 +21,8 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-#ifndef ARM_COMPUTE_NECONVOLUTIONLAYER_H
-#define ARM_COMPUTE_NECONVOLUTIONLAYER_H
+#ifndef ACL_ARM_COMPUTE_RUNTIME_NEON_FUNCTIONS_NECONVOLUTIONLAYER_H
+#define ACL_ARM_COMPUTE_RUNTIME_NEON_FUNCTIONS_NECONVOLUTIONLAYER_H
 
 #include "arm_compute/core/ITensorInfo.h"
 #include "arm_compute/core/Types.h"
@@ -38,7 +38,7 @@ namespace arm_compute
 class ITensor;
 
 /** Basic function to simulate a convolution layer. This function calls one of the following functions:
- * -# @ref cpu::CpuGemm     (executed only in case GEMM is required for the operation)
+ * -# @ref cpu::CpuGemmConv2d     (executed only in case GEMM is required for the operation)
  * -# @ref cpu::CpuWinogradConv2d (executed only in case Winograd is required for the operation)
  * -# @ref cpu::CpuDirectConv2d   (executed only in case Direct Convolution is required for the operation)
  * -# @ref NEFFTConvolutionLayer      (executed only in case FFT is required for the operation)
@@ -196,4 +196,4 @@ private:
     std::unique_ptr<Impl> _impl;
 };
 } // namespace arm_compute
-#endif /* ARM_COMPUTE_NECONVOLUTIONLAYER_H */
+#endif // ACL_ARM_COMPUTE_RUNTIME_NEON_FUNCTIONS_NECONVOLUTIONLAYER_H