Unable to build test-suite on Windows because of POSIX dependency

[ASDenysPetrov]

Bugzilla Link	45840
Version	10.0
OS	Windows NT
Attachments	test-suite build output
CC	@RKSimon

Extended Description

Current test-suite documentation https://llvm.org/docs/TestSuiteGuide.html does not describe setup process for Windows platforms, especially from the build step. I have tryed to fix it going down through build logs in console but new errors were appearing. It is unable to setup environment properly now.

Mainly the reason is that the main measurement source file ..test-suite\tools\timeit.c depends from POSIX includes like <sys/resource.h>

My suggestions would be to rewrite timeit.c in a cross-platform way.

Steps top reproduce:

1. Get test-suite from GitHub according to documentation
2. Run

mkdir test-suite-build
cd test-suite-build
cmake \
 -DCMAKE_C_COMPILER=<full path to llvm build>/bin/clang.exe \
 -DTEST_SUITE_HOST_CC=<full path to llvm build>/bin/clang.exe \
 -DCMAKE_LINKER=<full path to llvm build>/bin/lld.exe \
 -C../test-suite/cmake/caches/O0.cmake

3. Run

ninja

Output (shortened):

../tools/timeit.c:15:10: fatal error: 'sys/signal.h' file not found
#include <sys/signal.h>
         ^~~~~~~~~~~~~~
1 error generated.