saiislam added a comment. In D80804#2123183 <https://reviews.llvm.org/D80804#2123183>, @JonChesterfield wrote:
> This patch declares the clang builtin as acting on signed values, but the IR > intrinsic maps to an instruction which does an unsigned comparison. We don't > have ISA support for a signed comparison equivalent. Addition is the same > operation on signed or unsigned integers, but signed integer comparison is > not equivalent to unsigned integer comparison. > > // 32bit > tmp = MEM[ADDR]; > MEM[ADDR] = (tmp >= DATA) ? 0 : tmp + 1; // unsigned > compare > RETURN_DATA = tmp. > > > The builtins should be changed to take unsigned values, optionally making > that clear from the naming scheme, perhaps `__amdgcn_builtin_atomic_dec_u32`. > > Apologies for not reviewing this the first time around. I have created D83121 <https://reviews.llvm.org/D83121> for this. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D80804/new/ https://reviews.llvm.org/D80804 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
