[PATCH] D49503: [test-suite] Add Image Processing Kernels Using Benchmark Library: Dither Algorithms

[Michael Kruse via Phabricator via llvm-commits]

Meinersbur accepted this revision.
Meinersbur added a comment.
This revision is now accepted and ready to land.

What is the execution time of this?



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Comment at: MicroBenchmarks/ImageProcessing/Dither/main.cpp:36
+
+  initializeRandomImage((int *)*inputImage, HEIGHT, WIDTH);
+
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proton wrote:
> Meinersbur wrote:
> > Does this work? It dereferences the pointer returned by malloc (which should be the //uninitialized// first bytes of the memory allocated be malloc) and then casts it to a pointer. Id' expect this to result in a segfault.
> Yes, It works properly because the pointer returned by malloc is casted as **int (*) [][]**. So to access the array we have to first dereference the pointer (use it as (*inputImage)[i][j]).
Looks much better now


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Comment at: MicroBenchmarks/ImageProcessing/Dither/main.cpp:99
+  if (state.range(0) == 20) {
+    saveImage(outputImage, (const char *)"failedCase.txt", height, width);
+  }
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Could you add a comment that this exists to avoid the computation being optimized away?


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Comment at: MicroBenchmarks/ImageProcessing/Dither/main.cpp:148
+  if (state.range(0) == 20) {
+    saveImage(outputImage, (const char *)"failedCase.txt", height, width);
+  }
----------------
Here as well


https://reviews.llvm.org/D49503