update relu_kernel.mlir

[n0thingNoob]

Using the relu.cpp in for_loop to replace the original relu kernel

[Copilot]

Pull request overview

This PR updates the ReLU kernel test to use a C++ integer-based implementation (relu_int.cpp) instead of the previous C implementation (relu.c). The change simplifies the kernel and updates all test expectations accordingly.

Changes:

• Updated compilation from C (clang, C11) to C++ (clang++, C++17)
• Replaced source file from relu.c to relu_int.cpp
• Updated test expectations (MAPPING, YAML, ASM checks) to match the simpler integer-based ReLU kernel output

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[Copilot]

The FileCheck command for the MAPPING prefix is duplicated on line 29 and line 34. Line 34 appears to be redundant as line 29 already checks the same file with the same prefix. Consider removing the duplicate on line 34, or if both are intentional, add a comment explaining why the same check needs to run twice.

[Copilot]

The comment says "int ReLU" but doesn't specify what makes it different from the previous version. Consider adding more context about what "int ReLU" means (e.g., "integer-based ReLU" or "ReLU operating on integer arrays") to improve clarity for future readers.

Suggested change

	// Compile the int ReLU C++ kernel to LLVM IR.
	// Compile the integer-based ReLU C++ kernel (operating on integer arrays) to LLVM IR.

[tancheng]

Shouldn't we upload relu_int.cpp into testbench submodule and sync it in this PR?

[n0thingNoob]

Shouldn't we upload relu_int.cpp into testbench submodule and sync it in this PR?

Yes, I am doing that right now.