Changeset d7aa12c for src/Common/Eval.cc

Timestamp:

May 23, 2019, 11:55:32 AM (5 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, cleanup-dtors, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

b5fed34

Parents:

9d6e7fa9

Message:

Implemented eval for new AST

File:

• src/Common/Eval.cc (modified) (3 diffs)

src/Common/Eval.cc

@@ -17 +17 @@
 
 #include "Common/PassVisitor.h"
+#include "AST/Pass.hpp"
 #include "InitTweak/InitTweak.h"
 #include "SynTree/Expression.h"
 
-struct Eval : public WithShortCircuiting {
+//-------------------------------------------------------------
+// Old AST
+struct EvalOld : public WithShortCircuiting {
         long long int value = 0;
         bool valid = true;
@@ -80 +83 @@
 };
 
+//-------------------------------------------------------------
+// New AST
+struct EvalNew : public ast::WithShortCircuiting {
+        long long int value = 0;
+        bool valid = true;
+
+        void previsit( const ast::Node * ) { visit_children = false; }
+        void postvisit( const ast::Node * ) { valid = false; }
+
+        void postvisit( const ast::ConstantExpr * expr ) {
+                value = expr->intValue();
+        }
+
+        void postvisit( const ast::CastExpr * expr ) {
+                auto arg = eval(expr->arg);
+                valid = arg.second;
+                value = arg.first;
+                // TODO: perform type conversion on value if valid
+        }
+
+        void postvisit( const ast::VariableExpr * expr ) {
+                if ( const ast::EnumInstType * inst = dynamic_cast<const ast::EnumInstType *>(expr->result.get()) ) {
+                        if ( const ast::EnumDecl * decl = inst->base ) {
+                                if ( decl->valueOf( expr->var, value ) ) { // value filled by valueOf
+                                        return;
+                                }
+                        }
+                }
+                valid = false;
+        }
+
+        void postvisit( const ast::ApplicationExpr * expr ) {
+                const ast::DeclWithType * function = InitTweak::getFunction(expr);
+                if ( ! function || function->linkage != ast::Linkage::Intrinsic ) { valid = false; return; }
+                const std::string & fname = function->name;
+                assertf( expr->args.size() == 1 || expr->args.size() == 2, "Intrinsic function with %zd arguments: %s", expr->args.size(), fname.c_str() );
+                std::pair<long long int, bool> arg1, arg2;
+                arg1 = eval(expr->args.front());
+                valid = valid && arg1.second;
+                if ( ! valid ) return;
+                if ( expr->args.size() == 2 ) {
+                        arg2 = eval(expr->args.back());
+                        valid = valid && arg2.second;
+                        if ( ! valid ) return;
+                }
+                if (fname == "?+?") {
+                        value = arg1.first + arg2.first;
+                } else if (fname == "?-?") {
+                        value = arg1.first - arg2.first;
+                } else if (fname == "?*?") {
+                        value = arg1.first * arg2.first;
+                } else if (fname == "?/?") {
+                        value = arg1.first / arg2.first;
+                } else if (fname == "?%?") {
+                        value = arg1.first % arg2.first;
+                } else {
+                        valid = false;
+                }
+                // TODO: implement other intrinsic functions
+        }
+};
+
 std::pair<long long int, bool> eval(Expression * expr) {
-        PassVisitor<Eval> ev;
+        PassVisitor<EvalOld> ev;
         if (expr) {
                 expr->accept(ev);
@@ -91 +156 @@
 
 std::pair<long long int, bool> eval(const ast::Expr * expr) {
-        #warning not implemented
-        return { 0, false };
+        ast::Pass<EvalNew> ev;
+        if (expr) {
+                expr->accept(ev);
+                return std::make_pair(ev.pass.value, ev.pass.valid);
+        } else {
+                return std::make_pair(0, false);
+        }
 }