Cleanup c programs (#1620)

Cleanup C programs

programs/bpf/rust/noop/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "solana-bpf-noop"
+version = "0.11.0"
+description = "Solana BPF noop program"
+authors = ["Solana Maintainers <maintainers@solana.com>"]
+repository = "https://github.com/solana-labs/solana"
+license = "Apache-2.0"
+
+[dependencies]
+rbpf = "0.1.0"
+solana-sdk = { path = "../../../../sdk", version = "0.11.0" }

programs/bpf/rust/noop/build.sh

@@ -0,0 +1,10 @@
+#!/bin/bash -ex
+
+# TODO building release flavor with rust produces a bunch of output .bc files
+INTERDIR=../../../target/release
+OUTDIR="${1:-../../../target/debug/}"
+mkdir -p "$OUTDIR"
+# cargo +nightly rustc --release -- -C panic=abort --emit=llvm-ir
+cargo +nightly rustc --release -- -C panic=abort --emit=llvm-bc
+cp "$INTERDIR"/deps/noop_rust-*.bc "$OUTDIR"/noop_rust.bc 
+/usr/local/opt/llvm/bin/llc -march=bpf -filetype=obj -o "$OUTDIR"/noop_rust.o "$OUTDIR"/noop_rust.bc

programs/bpf/rust/noop/dump.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+/usr/local/opt/llvm/bin/llvm-objdump -color -source -disassemble target/release/noop_rust.o

programs/bpf/rust/noop/src/lib.rs

@@ -0,0 +1,15 @@
+extern crate rbpf;
+
+use std::mem::transmute;
+
+#[no_mangle]
+#[link_section = ".text,entrypoint"] // TODO platform independent needed
+pub extern "C" fn entrypoint(_raw: *mut u8) {
+    let bpf_func_trace_printk = unsafe {
+        transmute::<u64, extern "C" fn(u64, u64, u64, u64, u64)>(
+            rbpf::helpers::BPF_TRACE_PRINTK_IDX as u64,
+        )
+    };
+
+    bpf_func_trace_printk(0, 0, 1, 2, 3);
+}