RISC-V port and assorted changes
This commits adds code generation for the RISC-V architecture, both in 32- and 64-bit modes. The generated code was lightly tested using the simulator and cross-binutils from https://riscv.org/software-tools/ This port required the following additional changes: - Integers: More properties about shrx - SelectOp: now provides smart constructors for mulhs and mulhu - SelectDiv, 32-bit integer division and modulus: implement constant propagation, use the new smart constructors mulhs and mulhu. - Runtime library: if no asm implementation is provided, run the reference C implementation through CompCert. Since CompCert rejects the definitions of names of special functions such as __i64_shl, the reference implementation now uses "i64_" names, e.g. "i64_shl", and a renaming "i64_ -> __i64_" is performed over the generated assembly file, before assembling and building the runtime library. - test/: add SIMU make variable to run tests through a simulator - test/regression/alignas.c: make sure _Alignas and _Alignof are not #define'd by C headers commit da14495c01cf4f66a928c2feff5c53f09bde837f Author: Xavier Leroy <firstname.lastname@example.org> Date: Thu Apr 13 17:36:10 2017 +0200 RISC-V port, continued Now working on Asmgen. commit 36f36eb3a5abfbb8805960443d087b6a83e86005 Author: Xavier Leroy <email@example.com> Date: Wed Apr 12 17:26:39 2017 +0200 RISC-V port, first steps This port is based on Prashanth Mundkur's experimental RV32 port and brings it up to date with CompCert, and adds 64-bit support (RV64). Work in progress.