Share environment code between exe and sh backend (WIP)

diff-pnut-sh.sh

@@ -0,0 +1,38 @@
+#! /bin/sh
+
+set -e
+
+: ${PNUT_OPTIONS:=} # Default to empty options
+
+TEMP_DIR="build"
+PNUT_SH_OPTIONS="$PNUT_OPTIONS -DRT_NO_INIT_GLOBALS -Dsh"
+PNUT_SH_OPTIONS_FAST="$PNUT_SH_OPTIONS -DSH_SAVE_VARS_WITH_SET -DOPTIMIZE_CONSTANT_PARAM"
+PNUT_SH_FILE_ORIGINAL="$TEMP_DIR/pnut-sh-original.sh"
+PNUT_SH_FILE_FRESH="$TEMP_DIR/pnut-sh.sh"
+
+# Parse the arguments
+init=0
+
+while [ $# -gt 0 ]; do
+  case $1 in
+    --fast)  PNUT_SH_OPTIONS="$PNUT_SH_OPTIONS_FAST"; shift 1 ;;
+    --init)  init=1;                                  shift 1 ;;
+    *) echo "Unknown option: $1"; exit 1;;
+  esac
+done
+
+if [ ! -d "$TEMP_DIR" ]; then mkdir "$TEMP_DIR"; fi
+
+gcc -o "$TEMP_DIR/pnut.exe" $PNUT_SH_OPTIONS pnut.c
+
+if [ $init -eq 1 ]; then
+  ./$TEMP_DIR/pnut.exe $PNUT_SH_OPTIONS "pnut.c" > "$PNUT_SH_FILE_ORIGINAL"
+  exit 0
+fi
+
+if [ ! -f "$PNUT_SH_FILE_ORIGINAL" ]; then
+  echo "$PNUT_SH_FILE_ORIGINAL not found. Run this script with --init first."
+  exit 1
+fi
+./$TEMP_DIR/pnut.exe $PNUT_SH_OPTIONS "pnut.c" > "$PNUT_SH_FILE_FRESH"
+diff -w "$PNUT_SH_FILE_ORIGINAL" "$PNUT_SH_FILE_FRESH"

env.c

@@ -0,0 +1,198 @@
+int cgc_fs = 0;
+// Function bindings that follows lexical scoping rules
+int cgc_locals = 0;
+// Like cgc_locals, but with 1 scope for the entire function
+int cgc_locals_fun = 0;
+// Global bindings
+int cgc_globals = 0;
+// Bump allocator used to allocate static objects
+int cgc_global_alloc = 0;
+
+enum BINDING {
+  // Because function params, local and global variables all share the same
+  // namespace and we want to find the first one of them, we need to keep
+  // BINDING_PARAM_LOCAL, BINDING_VAR_LOCAL and BINDING_VAR_GLOBAL
+  // in consecutive order.
+  BINDING_PARAM_LOCAL,
+  BINDING_VAR_LOCAL,
+  BINDING_VAR_GLOBAL,
+  BINDING_ENUM_CST,
+  BINDING_LOOP,
+  BINDING_SWITCH,
+  BINDING_FUN,
+  BINDING_GOTO_LABEL,
+  BINDING_TYPE_STRUCT,
+  BINDING_TYPE_UNION,
+  BINDING_TYPE_ENUM,
+};
+
+int cgc_add_local(enum BINDING binding_type, int ident, int size, ast type) {
+  int binding = alloc_obj(6);
+  heap[binding+0] = cgc_locals;
+  heap[binding+1] = binding_type;
+  heap[binding+2] = ident;
+  heap[binding+3] = size;
+  heap[binding+4] = cgc_fs;
+  heap[binding+5] = type;
+  return binding;
+}
+
+void cgc_add_local_param(int ident, int size, ast type) {
+  cgc_locals = cgc_add_local(BINDING_PARAM_LOCAL, ident, size, type);
+#ifdef sh
+  cgc_fs += size;
+#else
+  cgc_fs -= size;
+#endif
+}
+
+void cgc_add_local_var(int ident, int size, ast type) {
+  cgc_fs += size;
+  cgc_locals = cgc_add_local(BINDING_VAR_LOCAL, ident, size, type);
+}
+
+void cgc_add_enclosing_loop(int loop_fs, int break_lbl, ast continue_lbl) {
+  int binding = alloc_obj(5);
+  heap[binding+0] = cgc_locals;
+  heap[binding+1] = BINDING_LOOP;
+  heap[binding+2] = loop_fs;
+  heap[binding+3] = break_lbl;
+  heap[binding+4] = continue_lbl;
+  cgc_locals = binding;
+}
+
+void cgc_add_enclosing_switch(int loop_fs, int break_lbl, int next_case_lbl) {
+  int binding = alloc_obj(5);
+  heap[binding+0] = cgc_locals;
+  heap[binding+1] = BINDING_SWITCH;
+  heap[binding+2] = loop_fs;
+  heap[binding+3] = break_lbl;
+  heap[binding+4] = next_case_lbl;
+  cgc_locals = binding;
+}
+
+void cgc_add_global(int ident, int size, int width, ast type) {
+  int binding = alloc_obj(6);
+  heap[binding+0] = cgc_globals;
+  heap[binding+1] = BINDING_VAR_GLOBAL;
+  heap[binding+2] = ident;
+  heap[binding+3] = size;
+  heap[binding+4] = cgc_global_alloc;
+  heap[binding+5] = type;
+  cgc_global_alloc += width;
+  cgc_globals = binding;
+}
+
+void cgc_add_global_fun(int ident, int label, ast type) {
+  int binding = alloc_obj(6);
+  heap[binding+0] = cgc_globals;
+  heap[binding+1] = BINDING_FUN;
+  heap[binding+2] = ident;
+  heap[binding+3] = 0;
+  heap[binding+4] = label;
+  heap[binding+5] = type;
+  cgc_globals = binding;
+}
+
+void cgc_add_enum(int ident, int value) {
+  int binding = alloc_obj(4);
+  heap[binding+0] = cgc_globals;
+  heap[binding+1] = BINDING_ENUM_CST;
+  heap[binding+2] = ident;
+  heap[binding+3] = value;
+  cgc_globals = binding;
+}
+
+void cgc_add_goto_label(int ident, int lbl) {
+  int binding = alloc_obj(5);
+  heap[binding+0] = cgc_locals_fun;
+  heap[binding+1] = BINDING_GOTO_LABEL;
+  heap[binding+2] = ident;
+  heap[binding+3] = lbl;
+  cgc_locals_fun = binding;
+}
+
+void cgc_add_typedef(int ident, enum BINDING struct_or_union_or_enum, ast type) {
+  int binding = alloc_obj(4);
+  heap[binding+0] = cgc_globals;
+  heap[binding+1] = struct_or_union_or_enum;
+  heap[binding+2] = ident;
+  heap[binding+3] = type;
+  cgc_globals = binding;
+}
+
+int cgc_lookup_binding_ident(int binding_type, int ident, int env) {
+  int binding = env;
+  while (binding != 0) {
+    if (heap[binding+1] == binding_type && heap[binding+2] == ident) {
+      break;
+    }
+    binding = heap[binding];
+  }
+  return binding;
+}
+
+int cgc_lookup_last_binding(int binding_type, int env) {
+  int binding = env;
+  while (binding != 0) {
+    if (heap[binding+1] == binding_type) {
+      break;
+    }
+    binding = heap[binding];
+  }
+  return binding;
+}
+
+int cgc_lookup_var(int ident, int env) {
+  int binding = env;
+  while (binding != 0) {
+    if (heap[binding+1] <= BINDING_VAR_GLOBAL && heap[binding+2] == ident) {
+      break;
+    }
+    binding = heap[binding];
+  }
+  return binding;
+}
+
+int cgc_lookup_fun(int ident, int env) {
+  return cgc_lookup_binding_ident(BINDING_FUN, ident, env);
+}
+
+int cgc_lookup_enclosing_loop(int env) {
+  return cgc_lookup_last_binding(BINDING_LOOP, env);
+}
+
+int cgc_lookup_enclosing_switch(int env) {
+  return cgc_lookup_last_binding(BINDING_SWITCH, env);
+}
+
+int cgc_lookup_enclosing_loop_or_switch(int env) {
+  int binding = env;
+  while (binding != 0) {
+    if (heap[binding+1] == BINDING_LOOP || heap[binding+1] == BINDING_SWITCH) {
+      break;
+    }
+    binding = heap[binding];
+  }
+  return binding;
+}
+
+int cgc_lookup_goto_label(int ident, int env) {
+  return cgc_lookup_binding_ident(BINDING_GOTO_LABEL, ident, env);
+}
+
+int cgc_lookup_struct(int ident, int env) {
+  return cgc_lookup_binding_ident(BINDING_TYPE_STRUCT, ident, env);
+}
+
+int cgc_lookup_union(int ident, int env) {
+  return cgc_lookup_binding_ident(BINDING_TYPE_UNION, ident, env);
+}
+
+int cgc_lookup_enum(int ident, int env) {
+  return cgc_lookup_binding_ident(BINDING_TYPE_ENUM, ident, env);
+}
+
+int cgc_lookup_enum_value(int ident, int env) {
+  return cgc_lookup_binding_ident(BINDING_ENUM_CST, ident, env);
+}

examples/compiled/repl.sh

@@ -445,16 +445,16 @@ _symbol_ref() { # n: $2
   : $((__tmp = $1)) $((n = $3)) $((__t1 = $4)) $(($1 = __tmp))
 }
 
-: $((__t2 = __t1 = root = sym = list = name = 0))
+: $((__t1 = root = sym = list = name = 0))
 _create_sym() { # name: $2
-  set $@ $name $list $sym $root $__t1 $__t2
+  set $@ $name $list $sym $root $__t1
   name=$2
-  _lst_length __t2 $name
-  _alloc_rib list $name $__t2 $(((3 << 1) | 1))
+  _lst_length __t1 $name
+  _alloc_rib list $name $__t1 $(((3 << 1) | 1))
   _alloc_rib sym $_FALSE $list $(((2 << 1) | 1))
   _alloc_rib root $sym $_symbol_table $(((0 << 1) | 1))
   : $(($1 = root))
-  : $((__tmp = $1)) $((name = $3)) $((list = $4)) $((sym = $5)) $((root = $6)) $((__t1 = $7)) $((__t2 = $8)) $(($1 = __tmp))
+  : $((__tmp = $1)) $((name = $3)) $((list = $4)) $((sym = $5)) $((root = $6)) $((__t1 = $7)) $(($1 = __tmp))
 }
 
 : $((__t1 = c = accum = n = 0))