* When we do the loop interchange on the one loop nest that get interchanged in the program source it is slightly (.7%) faster.
From: Gcc <gcc-bounces~visda.vokhshoori=microchip....@gcc.gnu.org> on behalf of Visda.Vokhshoori--- via Gcc <gcc@gcc.gnu.org> Date: Wednesday, February 12, 2025 at 10:38 AM To: gcc@gcc.gnu.org <gcc@gcc.gnu.org> Subject: 22% degradation seen in embench:matmult-int EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe Embench is used for benchmarking on embedded devices. This one project matmult-int has a function Multiply. It’s a matrix multiplication for 20 x 20 matrix. The device is a ATSAME70Q21B which is Cortex-M7 The compiler is arm branch based on GCC version 13 We are compiling with O3 which has loop-interchange pass on by default. When we compile with -fno-loop-interchange we get all 22% back plus 5% speed up. When we do the loop interchange on the one loop nest that get interchanged it is slightly (.7%) faster. Has anyone else seen large degradation as a result of loop interchange? Thanks
