feat：add initial support for precompile

emulator/src/state.rs

@@ -702,6 +702,10 @@ impl InstrumentedState {
                 log::trace!("set local user {:X} {:X} {:X}", a0, a1, a2);
                 self.state.local_user = a0;
             }
+            0xF2 => {
+                log::trace!("sys_verify {:X} {:X} {:X}", a0, a1, a2);
+                // DO Nothing Here
+            }
             _ => {}
         }
 

emulator/src/utils.rs

@@ -36,7 +36,7 @@ pub fn split_prog_into_segs(
             break;
         }
         let cycles = instrumented_state.step();
-        if cycles >= seg_size as u64 {
+        if cycles > (seg_size - 1) as u64 {
             instrumented_state.split_segment(true, seg_path, new_writer);
         }
     }

prover/examples/README.md

@@ -88,3 +88,23 @@ Or
 
 RUST_LOG=info ELF_PATH=examples/revme/target/mips-unknown-linux-musl/release/evm HOST_PROGRAM=revm JSON_PATH=../emulator/test-vectors/test.json SEG_OUTPUT=/tmp/output SEG_SIZE=262144 cargo run --release --example zkmips prove_host_program
 ```
+
+## Prove precompile code
+* Build the sha2-rust
+```
+cd prover/examples/sha2-rust
+cargo build -r --target=mips-unknown-linux-musl
+```
+
+* Build the sha2-precompile
+```
+cd prover/examples/sha2-precompile
+cargo build -r --target=mips-unknown-linux-musl
+```
+
+* Run the host program
+```
+cd ../..
+
+RUST_LOG=info PRECOMPILE_PATH=examples/sha2-rust/target/mips-unknown-linux-musl/release/sha2-rust ELF_PATH=examples/sha2-precompile/target/mips-unknown-linux-musl/release/sha2-precompile HOST_PROGRAM=sha2_precompile SEG_OUTPUT=/tmp/output cargo run --release --example zkmips prove_host_program
+```

prover/examples/sha2-precompile/Cargo.toml

@@ -0,0 +1,10 @@
+[workspace]
+[package]
+version = "0.1.0"
+name = "sha2-precompile"
+edition = "2021"
+
+[dependencies]
+# zkm-runtime = { git = "https://github.com/zkMIPS/zkm", package = "zkm-runtime" }
+zkm-runtime = { path = "../../../runtime/entrypoint" }
+sha2 = { version = "0.10.8", default-features = false }

prover/examples/sha2-precompile/rust-toolchain.toml

@@ -0,0 +1,4 @@
+[toolchain]
+channel = "nightly-2023-04-06"
+targets = ["mips-unknown-linux-musl"]
+profile = "minimal"