momchil-velikov wrote: > > This patch adds instcombine to some tests that were passing > Can the instcombines be replaced with something simpler like dce or maybe > instsimplify? It might be OK with just mem2reg.
Unfortunately just `mem2reg` does not cut it. The original issue it that Clang generates very different code for C-style cast and `__builtin_bit_cast`, e.g. for (https://gcc.godbolt.org/z/7rKqhTY5W) ``` typedef __attribute__((neon_vector_type(4))) unsigned uint32x4_t; typedef __attribute__((neon_vector_type(4))) float float32x4_t; uint32x4_t f(float32x4_t v) { return __builtin_bit_cast(uint32x4_t ,v); } uint32x4_t g(float32x4_t v) { return (uint32x4_t) v; } ``` and the differences persist after `mem2reg` : ``` define dso_local <4 x i32> @f(<4 x float> noundef %v) #0 { entry: %v.addr = alloca <4 x float>, align 16 store <4 x float> %v, ptr %v.addr, align 16 %0 = load <4 x i32>, ptr %v.addr, align 16 ret <4 x i32> %0 } define dso_local <4 x i32> @g(<4 x float> noundef %v) #0 { entry: %0 = bitcast <4 x float> %v to <4 x i32> ret <4 x i32> %0 } ``` which makes the test updates after https://github.com/llvm/llvm-project/pull/121802 very hard to inspect. I can try with `sroa` instead of `instcombine` (works on this example above at least) https://github.com/llvm/llvm-project/pull/121801 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
