spatel added a comment. In D69979#1749198 <https://reviews.llvm.org/D69979#1749198>, @arsenm wrote:
> I just posted the test I wrote here: https://github.com/arsenm/subnormal_test Thanks. I tried compiling with gcc (can't trust clang since it doesn't honor #pragma STDC FENV_ACCESS ON?). And running that on a Ubuntu 17.10 x86-64 system, it's behaving as I would expect. If you compile without -ffast-math, it asserts: With denormals disabled a.out: subnormal_test.cpp:33: void fp32_denorm_test(): Assertion `std::fpclassify(subnormal) == FP_SUBNORMAL' failed. And if you compile with -ffast-math, it asserts: In default FP mode a.out: subnormal_test.cpp:33: void fp32_denorm_test(): Assertion `std::fpclassify(subnormal) == FP_SUBNORMAL' failed. This is what I see compiling Craig's csr tester: $ cc -O2 csr.c && ./a.out 1f80 $ cc -O2 csr.c -ffast-math && ./a.out 9fc0 FZ is bit 15 (0x8000) and DAZ is bit 6 (0x0040), so they are clear in default (IEEE) mode and set with -ffast-math. CHANGES SINCE LAST ACTION https://reviews.llvm.org/D69979/new/ https://reviews.llvm.org/D69979 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits