Implement meta-mutants

Squashed commit of the following:

commit 8701315
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Thu Mar 10 13:55:56 2022 +0100

    Make number of allocated globals for saved parameters adaptive

commit b26afdc
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Thu Mar 10 13:11:50 2022 +0100

    Refactoring

commit 025fc9e
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Thu Mar 10 12:58:07 2022 +0100

    Refactor meta-mutant implementation

commit a621c12
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Mon Mar 7 16:33:43 2022 +0100

    Add configuration option for meta-mutants

commit 5ce4b3c
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Mon Mar 7 14:42:07 2022 +0100

    Update dependencies

commit 6427ec7
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Sun Mar 6 19:15:55 2022 +0100

    Meta mutants mostly work now

commit a5191e8
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Sun Mar 6 14:38:22 2022 +0100

    More work toward meta-mutants

commit f5682e1
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Thu Mar 3 10:14:04 2022 +0100

    Checkpoint

commit 968579d
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Wed Mar 2 16:47:42 2022 +0100

    Some preliminary refactoring necessary for meta-mutants

commit 5c0c8d2
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Wed Feb 23 19:46:18 2022 +0100

    Start implementation of mutate_all function

commit 8f52921
Author: Lukas Wagner <lwagner94@posteo.at>
Date:   Wed Feb 23 16:10:37 2022 +0100

    Add check_mutant_id api function, add unique mutant id, add result_type for operators

Cargo.toml

@@ -37,23 +37,23 @@ clap = {version = "3.0.0", features=["cargo", "derive"]}
 object = { version = "0.28.1", features = ["read", "wasm"]}
 addr2line = "0.17.0"
 gimli = "0.26.1"
-
 toml = "0.5.0"
 serde = { version = "1.0", features = ["derive"] }
-
 colored = "2.0.0"
 log = "0.4.0"
 env_logger = "0.9.0"
 num_cpus = "1.13.1"
 indicatif = {version = "0.16.2", features = ["rayon"]}
 rand = "0.8.4"
-
 syntect = "4.6.0"
-
 handlebars = "4.2.0"
 md5 = "0.7.0"
 concat-idents = "1.1.3"
 chrono = "0.4.19"
+atomic-counter = "1.0.1"
+dyn-clone = "1.0.4"
+
 [dev-dependencies]
 tempfile = "3.3.0"
 quickcheck = "1.0.3"
+pretty_assertions = "1.0.3"

README.md

@@ -329,7 +329,17 @@ for any hints on what compiler options to use.
     Defaults to `true`.
 
     ```toml
-    coverage_based_execution = false
+    coverage_based_execution = true
+    ```
+
+  - `meta_mutant`:
+    If `meta_mutant` is enabled, a single mutant containing all mutations will be generated.
+    During execution, mutations are activated by setting a flag. The benefit
+    of this is that only a single mutant needs to be compiled by the WebAssembly runtime,
+    and thus the execution time is reduced significantly.
+    Defaults to `true`.
+    ```toml
+    meta_mutant = true
     ```
 
 
@@ -377,6 +387,7 @@ for any hints on what compiler options to use.
 timeout_multiplier = 4.0
 map_dirs = [["testdata/count_words/files", "files"],]
 coverage_based_execution = true
+meta_mutant = true
 
 [filter]
 allowed_functions = ["^count_words"]

src/cliarguments.rs

@@ -73,6 +73,7 @@ pub enum CLICommand {
         /// Path to the wasm module
         wasmfile: String,
     },
+
     /// Create new configuration file.
     NewConfig {
         /// Path to the new configuration file

src/config.rs

@@ -43,6 +43,11 @@ pub struct EngineConfig {
     /// line was never executed in the baseline run.
     /// Defaults to true
     coverage_based_execution: Option<bool>,
+
+    /// If true, a single mutant containing all mutations will be generated.
+    /// During execution, mutations are activated by setting a flag
+    /// Defaults to true.
+    meta_mutant: Option<bool>,
 }
 
 impl EngineConfig {
@@ -64,6 +69,11 @@ impl EngineConfig {
     pub fn coverage_based_execution(&self) -> bool {
         self.coverage_based_execution.unwrap_or(true)
     }
+
+    /// Generate a single meta-mutant
+    pub fn meta_mutant(&self) -> bool {
+        self.meta_mutant.unwrap_or(true)
+    }
 }
 
 /// Configuration regarding report generation
@@ -214,10 +224,12 @@ mod tests {
             timeout_multiplier = 10
             map_dirs = [["a/foo", "b/bar"], ["abcd", "abcd"]]
             coverage_based_execution = false
+            meta_mutant = false
             "#,
         )?;
         assert_eq!(config.engine().timeout_multiplier(), 10.0);
         assert!(!config.engine().coverage_based_execution());
+        assert!(!config.engine().meta_mutant());
         assert_eq!(
             config.engine().map_dirs(),
             [
@@ -281,6 +293,7 @@ mod tests {
         )?;
         assert_eq!(config.engine().timeout_multiplier(), 2.0);
         assert!(config.engine().coverage_based_execution());
+        assert!(config.engine().meta_mutant());
         assert_eq!(config.engine().map_dirs(), []);
         assert_eq!(config.filter().allowed_files(), None);
         assert_eq!(config.filter().allowed_functions(), None);