From 94f7b8c07623398460227576a84c3e249868feff Mon Sep 17 00:00:00 2001
From: jonboh <jon.bosque.hernando@gmail.com>
Date: Tue, 2 Jan 2024 18:45:04 +0100
Subject: [PATCH] add llvm-path option

this allows the usage of an already installed llvm-profdata binary
---
 src/options/coverage.rs |  6 ++++++
 src/project.rs          | 20 +++++++++++++++-----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/options/coverage.rs b/src/options/coverage.rs
index bf66e38..4c416c8 100644
--- a/src/options/coverage.rs
+++ b/src/options/coverage.rs
@@ -1,3 +1,5 @@
+use std::path::PathBuf;
+
 use crate::{
     options::{BuildOptions, FuzzDirWrapper},
     project::FuzzProject,
@@ -14,6 +16,10 @@ pub struct Coverage {
     #[command(flatten)]
     pub fuzz_dir_wrapper: FuzzDirWrapper,
 
+    /// Sets the path to the LLVM bin directory. By default, it will use the one installed with rustc
+    #[arg(long)]
+    pub llvm_path: Option<PathBuf>,
+
     /// Name of the fuzz target
     pub target: String,
 
diff --git a/src/project.rs b/src/project.rs
index 61a9649..306df37 100644
--- a/src/project.rs
+++ b/src/project.rs
@@ -699,7 +699,14 @@ impl FuzzProject {
                 .context("Failed to generage coverage data")?;
             }
         }
-        self.merge_coverage(&coverage_out_raw_dir, &coverage_out_file)?;
+
+        let mut profdata_bin_path = coverage.llvm_path.clone().unwrap_or(rustlib()?);
+        profdata_bin_path.push(format!("llvm-profdata{}", env::consts::EXE_SUFFIX));
+        self.merge_coverage(
+            &profdata_bin_path,
+            &coverage_out_raw_dir,
+            &coverage_out_file,
+        )?;
 
         Ok(())
     }
@@ -749,10 +756,13 @@ impl FuzzProject {
         Ok((cmd, dummy_corpus))
     }
 
-    fn merge_coverage(&self, profdata_raw_path: &Path, profdata_out_path: &Path) -> Result<()> {
-        let mut profdata_path = rustlib()?;
-        profdata_path.push(format!("llvm-profdata{}", env::consts::EXE_SUFFIX));
-        let mut merge_cmd = Command::new(profdata_path);
+    fn merge_coverage(
+        &self,
+        profdata_bin_path: &Path,
+        profdata_raw_path: &Path,
+        profdata_out_path: &Path,
+    ) -> Result<()> {
+        let mut merge_cmd = Command::new(profdata_bin_path);
         merge_cmd.arg("merge").arg("-sparse");
         merge_cmd.arg(profdata_raw_path);
         merge_cmd.arg("-o").arg(profdata_out_path);