From 208509bec179ac5fe924657a2ba9df45a573264f Mon Sep 17 00:00:00 2001
From: kunxian xia <xiakunxian130@gmail.com>
Date: Tue, 29 Oct 2024 11:54:50 +0800
Subject: [PATCH] address comments

---
 Cargo.lock              | 13 -------------
 Cargo.toml              |  2 --
 ceno_emul/Cargo.toml    |  2 --
 ceno_emul/src/elf.rs    | 20 ++++++++++++++------
 ceno_emul/src/rv32im.rs |  3 +--
 5 files changed, 15 insertions(+), 25 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 09cd4ec9e..c80dfdedb 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -241,8 +241,6 @@ dependencies = [
  "anyhow",
  "ceno-examples",
  "elf",
- "num-derive",
- "num-traits",
  "strum",
  "strum_macros",
  "tracing",
@@ -1120,17 +1118,6 @@ dependencies = [
  "rand",
 ]
 
-[[package]]
-name = "num-derive"
-version = "0.4.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed3955f1a9c7c0c15e092f9c887db08b1fc683305fdf6eb6684f22555355e202"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.82",
-]
-
 [[package]]
 name = "num-format"
 version = "0.4.4"
diff --git a/Cargo.toml b/Cargo.toml
index b69a91ef0..aea908372 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -31,8 +31,6 @@ crossbeam-channel = "0.5"
 ff = "0.13"
 goldilocks = { git = "https://github.com/hero78119/Goldilocks" }
 itertools = "0.13"
-num-traits = "0.2"
-num-derive = "0.4"
 paste = "1"
 plonky2 = "0.2"
 poseidon = { path = "./poseidon" }
diff --git a/ceno_emul/Cargo.toml b/ceno_emul/Cargo.toml
index 6b93a3f0a..8f78e5805 100644
--- a/ceno_emul/Cargo.toml
+++ b/ceno_emul/Cargo.toml
@@ -7,8 +7,6 @@ version.workspace = true
 [dependencies]
 anyhow = { version = "1.0", default-features = false }
 elf = "0.7"
-num-derive.workspace = true
-num-traits.workspace = true
 strum.workspace = true
 strum_macros.workspace = true
 tracing.workspace = true
diff --git a/ceno_emul/src/elf.rs b/ceno_emul/src/elf.rs
index 9a1c8742b..21d12779f 100644
--- a/ceno_emul/src/elf.rs
+++ b/ceno_emul/src/elf.rs
@@ -59,7 +59,7 @@ impl Program {
     pub fn load_elf(input: &[u8], max_mem: u32) -> Result<Program> {
         let mut instructions: Vec<u32> = Vec::new();
         let mut image: BTreeMap<u32, u32> = BTreeMap::new();
-        let mut base_address = max_mem;
+        let mut base_address = None;
 
         let elf = ElfBytes::<LittleEndian>::minimal_parse(input)
             .map_err(|err| anyhow!("Elf parse error: {err}"))?;
@@ -92,9 +92,9 @@ impl Program {
             tracing::debug!(
                 "loadable segement {}: PF_R={}, PF_W={}, PF_X={}",
                 idx,
-                segment.p_flags & PF_R,
-                segment.p_flags & PF_W,
-                segment.p_flags & PF_X,
+                segment.p_flags & PF_R != 0,
+                segment.p_flags & PF_W != 0,
+                segment.p_flags & PF_X != 0,
             );
             let file_size: u32 = segment
                 .p_filesz
@@ -114,8 +114,12 @@ impl Program {
                 .p_vaddr
                 .try_into()
                 .map_err(|err| anyhow!("vaddr is larger than 32 bits. {err}"))?;
-            if (segment.p_flags & PF_X) != 0 && base_address > vaddr {
-                base_address = vaddr;
+            if (segment.p_flags & PF_X) != 0 {
+                if base_address.is_none() {
+                    base_address = Some(vaddr);
+                } else {
+                    return Err(anyhow!("only support one executable segment"));
+                }
             }
             if vaddr % WORD_SIZE as u32 != 0 {
                 bail!("vaddr {vaddr:08x} is unaligned");
@@ -151,6 +155,10 @@ impl Program {
             }
         }
 
+        if base_address.is_none() {
+            return Err(anyhow!("does not have executable segment"));
+        }
+        let base_address = base_address.unwrap();
         assert!(entry >= base_address);
         assert!((entry - base_address) as usize <= instructions.len() * WORD_SIZE);
 
diff --git a/ceno_emul/src/rv32im.rs b/ceno_emul/src/rv32im.rs
index b7618aad0..0ce557be2 100644
--- a/ceno_emul/src/rv32im.rs
+++ b/ceno_emul/src/rv32im.rs
@@ -15,7 +15,6 @@
 // limitations under the License.
 
 use anyhow::{Result, anyhow};
-use num_derive::ToPrimitive;
 use std::sync::OnceLock;
 use strum_macros::EnumIter;
 
@@ -135,7 +134,7 @@ pub enum InsnFormat {
 }
 use InsnFormat::*;
 
-#[derive(Clone, Copy, Debug, PartialEq, EnumIter, ToPrimitive)]
+#[derive(Clone, Copy, Debug, PartialEq, EnumIter)]
 #[allow(clippy::upper_case_acronyms)]
 pub enum InsnKind {
     INVALID,