This patch adds a new set of conformance tests for single-precision math
functions provided by the LLVM libm for GPUs.
The functions included in this set were selected based on the following
criteria:
- An implementation exists in `libc/src/math/generic` (i.e., it is not
just a wrapper around a compiler built-in).
- The corresponding LLVM CPU libm implementation is correctly rounded.
- The function is listed in Table 65 of the OpenCL C Specification
v3.0.19.
This PR introduces the initial version of a C++ framework for the
conformance testing of GPU math library functions, building upon the
skeleton provided in #146391.
The main goal of this framework is to systematically measure the
accuracy of math functions in the GPU libc, verifying correctness or at
least conformance to standards like OpenCL via exhaustive or random
accuracy tests.
