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Intel OpenCL compiler (aoc) does not coalesce global memory reads anymore

Björne2
Novice
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The two screenshots says it all. The old screenshot is generated with aoc 21.2.0. Note how it coalesces the 16 float reads into one 512 bit DDR read. The new screenshot is generated with aoc 2024.2.1. It does not coalesce the 16 float reads and instead creates 16 individual read ports. Afaict, that is quite bad for performance and it wastes a lot of hardware resources.

 

Is there a way to make aoc 2024.2.1 coalesce, exactly like the old compiler did?

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yuguen
Employee
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The OpenCL SDK for Intel FPGAs is no longer distributed since 22.4.

Therefore, 22.4 is the last version of the compiler to officially support OpenCL as an input language.

 

How did you get a 2024.2.1 version of aoc? I'm guessing that you got that binary from a oneAPI SYCL compiler for FPGA install.

The SYCL compiler uses aoc internally, but is not expected to work as a standalone.

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