[RISCV] Use compiler-rt if no GCC installation detected
authorEdward Jones <ed.jones@embecosm.com>
Fri, 22 Nov 2019 19:05:39 +0000 (19:05 +0000)
committerEdward Jones <ed.jones@embecosm.com>
Fri, 22 Nov 2019 20:05:29 +0000 (20:05 +0000)
commite0f22fe04a5c9eb244ff0533549743b7deb03b99
treec15d57541321863291ddc3aee49e7fc300a5b65f
parent262b10ba1f9db4d00f43bcb1d8c1e557dced3bcd
[RISCV] Use compiler-rt if no GCC installation detected

If a GCC installation is not detected, then this attempts to
use compiler-rt and the compiler-rt crtbegin/crtend
implementations as a fallback.

Differential Revision: https://reviews.llvm.org/D68407
clang/lib/Driver/ToolChains/RISCVToolchain.cpp
clang/lib/Driver/ToolChains/RISCVToolchain.h
clang/test/Driver/riscv32-toolchain-extra.c
clang/test/Driver/riscv32-toolchain.c
clang/test/Driver/riscv64-toolchain-extra.c
clang/test/Driver/riscv64-toolchain.c