cleanup code generation, add throw/catch, copy_term, var, atomic, not, false builtins

2017-08-13 23:53:01 -06:00
parent 198eca678c
commit a06d99a313
14 changed files with 908 additions and 296 deletions
--- a/src/prolog/builtins.rs
+++ b/src/prolog/builtins.rs
@@ -0,0 +1,125 @@
+use prolog::ast::*;
+
+use std::collections::HashMap;
+
+pub type PredicateKey = (Atom, usize); // name, arity, type.
+
+#[derive(Clone, Copy, PartialEq, Eq, Hash)]
+pub enum PredicateKeyType {
+    BuiltIn,
+    User
+}
+
+pub type CodeDir = HashMap<PredicateKey, (PredicateKeyType, usize)>;
+     
+fn get_builtins() -> Code {    
+    vec![internal_call_n!(), // callN/N, 0.
+         is_atomic!(), // atomic/1, 1.
+         proceed!(),
+         is_var!(),    // var/1, 3.
+         proceed!(),
+         allocate!(4), // catch/3, 5.
+         query![get_var_in_query!(perm_v!(2), 1),
+                get_var_in_query!(perm_v!(3), 2),
+                get_var_in_query!(perm_v!(1), 3),
+                put_var!(perm_v!(4), 1)],
+         get_current_block!(),
+         query![put_value!(perm_v!(2), 1),
+                put_value!(perm_v!(3), 2),
+                put_value!(perm_v!(1), 3),
+                put_unsafe_value!(4, 4)],
+         deallocate!(),
+         goto!(11, 4),
+         try_me_else!(9), // catch/4, 11.
+         allocate!(3),
+         query![get_var_in_query!(perm_v!(3), 1),
+                get_var_in_query!(perm_v!(2), 4),
+                put_var!(perm_v!(1), 1)],
+         install_new_block!(),
+         query![put_value!(perm_v!(3), 1)],
+         call_n!(1),
+         query![put_value!(perm_v!(2), 1),
+                put_unsafe_value!(1, 2)],
+         deallocate!(),
+         goto!(42, 2), // goto end_block/2 at 42.
+         trust_me!(),
+         allocate!(4),
+         query![get_var_in_query!(perm_v!(2), 2),
+                get_var_in_query!(perm_v!(1), 3),
+                get_var_in_query!(temp_v!(2), 1),
+                put_value!(temp_v!(4), 1)],
+         reset_block!(),
+         query![put_var!(perm_v!(4), 1)],
+         get_ball!(),
+         query![put_value!(perm_v!(4), 1),
+                put_var!(perm_v!(3), 2)],
+         copy_term!(),
+         query![put_unsafe_value!(3, 1),
+                put_value!(perm_v!(2), 2),
+                put_value!(perm_v!(1), 3)],
+         deallocate!(),
+         goto!(31, 2), // goto handle_ball/2.
+         try_me_else!(10), // handle_ball/2, 31.
+         allocate!(2),
+         get_level!(),
+         query![get_var_in_query!(perm_v!(2), 3)],
+         unify!(),
+         cut!(non_terminal!()),
+         query![put_value!(perm_v!(2), 1)],
+         deallocate!(),
+         execute_n!(1),
+         trust_me!(),
+         unwind_stack!(),
+         try_me_else!(8), // end_block/2, 42.
+         allocate!(1),
+         query![get_var_in_query!(perm_v!(1), 1),
+                put_value!(temp_v!(2), 1)],
+         clean_up_block!(),
+         query![put_value!(perm_v!(1), 1)],
+         deallocate!(),
+         reset_block!(),
+         proceed!(),
+         trust_me!(),
+         allocate!(0),
+         query![get_var_in_query!(temp_v!(3), 1),
+                put_value!(temp_v!(2), 1)],
+         reset_block!(),
+         deallocate!(),
+         goto!(58, 0), // goto false.
+         set_ball!(), // throw/1, 56.
+         unwind_stack!(),         
+         fail!(), // false/0, 58.
+         proceed!(),
+         try_me_else!(7), // not/1, 60.
+         allocate!(1),
+         get_level!(),
+         call_n!(1),
+         cut!(non_terminal!()),
+         deallocate!(),
+         goto!(58, 0), // goto false.
+         trust_me!(),
+         proceed!(),
+         copy_term!(), // copy_term/2, 69.
+         proceed!()]
+}
+
+pub fn build_code_dir() -> (Code, CodeDir) {
+    let mut code_dir = HashMap::new();
+    let builtin_code = get_builtins();
+    
+    // there are 63 registers in the VM, so call/N is defined for all 0 <= N <= 62
+    // (an extra register is needed for the predicate name)
+    for arity in 0 .. 63 {
+        code_dir.insert((String::from("call"), arity), (PredicateKeyType::BuiltIn, 0));
+    }
+
+    code_dir.insert((String::from("atomic"), 1), (PredicateKeyType::BuiltIn, 1));
+    code_dir.insert((String::from("var"), 1), (PredicateKeyType::BuiltIn, 3));
+    code_dir.insert((String::from("false"), 0), (PredicateKeyType::BuiltIn, 58));
+    code_dir.insert((String::from("not"), 1), (PredicateKeyType::BuiltIn, 60));
+    code_dir.insert((String::from("copy_term"), 2), (PredicateKeyType::BuiltIn, 69));
+    code_dir.insert((String::from("catch"), 3), (PredicateKeyType::BuiltIn, 5));
+    code_dir.insert((String::from("throw"), 1), (PredicateKeyType::BuiltIn, 56));
+
+    (builtin_code, code_dir)
+}