Re-org SDK dir (#4690)

sdk/bpf/rust/build.sh

@@ -0,0 +1,43 @@
+#!/usr/bin/env bash
+
+if [ "$#" -ne 1 ]; then
+    echo "Error: Must provide the full path to the project to build"
+    exit 1
+fi
+if [ ! -f "$1/Cargo.toml" ]; then
+      echo "Error: Cannot find project: $1"
+    exit 1
+fi
+
+cd "$(dirname "$0")"
+bpf_sdk="$PWD/.."
+export XARGO_HOME="$PWD/../../../target/xargo"
+
+cd "$1"
+
+cargo install xargo
+
+set -e
+
+# Ensure the sdk is installed
+"$bpf_sdk"/scripts/install.sh
+
+# Use the SDK's version of llvm to build the compiler-builtins for BPF
+export CC="$bpf_sdk/dependencies/llvm-native/bin/clang"
+export AR="$bpf_sdk/dependencies/llvm-native/bin/llvm-ar"
+# Use the SDK's version of Rust to build for BPF
+export RUSTUP_TOOLCHAIN=bpf
+export RUSTFLAGS="
+    --emit=llvm-ir \
+    -C lto=no \
+    -C opt-level=2 \
+    -C link-arg=-z -C link-arg=notext \
+    -C link-arg=-T$bpf_sdk/rust/bpf.ld \
+    -C link-arg=--Bdynamic \
+    -C link-arg=-shared \
+    -C link-arg=--entry=entrypoint \
+    -C linker=$bpf_sdk/dependencies/llvm-native/bin/ld.lld"
+export XARGO_RUST_SRC="$bpf_sdk/dependencies/rust-bpf-sysroot/src"
+xargo build --target bpfel-unknown-unknown --release -v
+
+{ { set +x; } 2>/dev/null; echo Success; }