RISC-V LLVM Templates

This repo is similar to riscv-probe but utilizes the LLVM toolchain instead of the GNU toolchain.

Contains

• Makefile
  • LLVM invocations
• Linker Script
  • Virtual memory map
  • Layout of the executable
• Assembly
  • Setting the stack pointer
  • Calling main()
  • Calling exit()
• C
  • Minimal host / target interface
  • Classical "Hello World!"

Usage

Set the LLVM and RISCV environment variables if you haven't installed the prerequisites at their defaults.

• make to build all targets
• make clean to delete all targets
• To show the targets disassembly, sections, symbols, etc:
  • make dump.spike
  • make dump.rv8
• To run it:
  • make run.spike
  • make run.qemu
  • make run.rv8

Prerequisites

You will need this repo, the llvm toolchain compiled with the experimental RISC-V target and at least one of the three simulators / emulators listed below.

LLVM

git clone https://git.llvm.org/git/llvm.git
cd llvm/tools
git clone https://git.llvm.org/git/clang.git
git clone https://git.llvm.org/git/lld.git
cd ../..
mv llvm llvmSrc
mkdir llvm
cd llvm
cmake -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD="RISCV" -DLLVM_LINK_LLVM_DYLIB=ON ../llvmSrc/
make -j8 clang llc lld llvm-objdump llvm-readobj

Simulators / Emulators

• Spike
  • device tree compiler
  • frontend server
  • isa simulator
• qemu
• rv8