address comments

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" }

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

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);
 

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,