WIP: Implementing Symbolic ASR pass

src/libasr/CMakeLists.txt

@@ -48,6 +48,7 @@ set(SRC
     pass/unused_functions.cpp
     pass/flip_sign.cpp
     pass/div_to_mul.cpp
+    pass/replace_symbolic.cpp
     pass/intrinsic_function.cpp
     pass/fma.cpp
     pass/loop_vectorise.cpp

src/libasr/gen_pass.py

@@ -12,6 +12,7 @@
         "replace_implied_do_loops",
         "replace_init_expr",
         "inline_function_calls",
+        "replace_symbolic",
         "replace_intrinsic_function",
         "loop_unroll",
         "loop_vectorise",

src/libasr/pass/pass_manager.h

@@ -28,6 +28,7 @@
 #include <libasr/pass/replace_arr_slice.h>
 #include <libasr/pass/replace_flip_sign.h>
 #include <libasr/pass/replace_div_to_mul.h>
+#include <libasr/pass/replace_symbolic.h>
 #include <libasr/pass/replace_intrinsic_function.h>
 #include <libasr/pass/replace_fma.h>
 #include <libasr/pass/loop_unroll.h>
@@ -71,6 +72,7 @@ namespace LCompilers {
             {"global_stmts", &pass_wrap_global_stmts},
             {"implied_do_loops", &pass_replace_implied_do_loops},
             {"array_op", &pass_replace_array_op},
+            {"symbolic", &pass_replace_symbolic},
             {"intrinsic_function", &pass_replace_intrinsic_function},
             {"arr_slice", &pass_replace_arr_slice},
             {"print_arr", &pass_replace_print_arr},
@@ -203,6 +205,7 @@ namespace LCompilers {
                 "subroutine_from_function",
                 "where",
                 "array_op",
+                "symbolic",
                 "intrinsic_function",
                 "array_op",
                 "pass_array_by_data",

src/libasr/pass/replace_symbolic.cpp

@@ -0,0 +1,165 @@
+#include <libasr/asr.h>
+#include <libasr/containers.h>
+#include <libasr/exception.h>
+#include <libasr/asr_utils.h>
+#include <libasr/asr_verify.h>
+#include <libasr/pass/replace_symbolic.h>
+#include <libasr/pass/pass_utils.h>
+
+#include <vector>
+
+
+namespace LCompilers {
+
+using ASR::down_cast;
+using ASR::is_a;
+
+
+class ReplaceSymbolicVisitor : public PassUtils::PassVisitor<ReplaceSymbolicVisitor>
+{
+public:
+    ReplaceSymbolicVisitor(Allocator &al_) :
+    PassVisitor(al_, nullptr) {
+        pass_result.reserve(al, 1);
+    }
+
+    bool symbolic_replaces_with_CPtr_Function = false;
+
+    void visit_Function(const ASR::Function_t &x) {
+        // FIXME: this is a hack, we need to pass in a non-const `x`,
+        // which requires to generate a TransformVisitor.
+        ASR::Function_t &xx = const_cast<ASR::Function_t&>(x);
+        SymbolTable* current_scope_copy = this->current_scope;
+        this->current_scope = xx.m_symtab;
+        for (auto &item : x.m_symtab->get_scope()) {
+            if (ASR::is_a<ASR::Variable_t>(*item.second)) {
+                ASR::Variable_t *s = ASR::down_cast<ASR::Variable_t>(item.second);
+                this->visit_Variable(*s);
+            }
+        }
+        transform_stmts(xx.m_body, xx.n_body);
+
+        // Add "basic_new_stack" to dependencies if needed
+        if (symbolic_replaces_with_CPtr_Function) {
+            SetChar function_dependencies;
+            function_dependencies.n = 0;
+            function_dependencies.reserve(al, 1);
+            for( size_t i = 0; i < xx.n_dependencies; i++ ) {
+                function_dependencies.push_back(al, xx.m_dependencies[i]);
+            }
+            function_dependencies.push_back(al, s2c(al, "basic_new_stack"));
+            xx.n_dependencies = function_dependencies.size();
+            xx.m_dependencies = function_dependencies.p;
+        }
+        this->current_scope = current_scope_copy;
+    }
+
+    void visit_Variable(const ASR::Variable_t& x) {
+        ASR::Variable_t& xx = const_cast<ASR::Variable_t&>(x);
+        SymbolTable* current_scope_copy = current_scope;
+        current_scope = xx.m_parent_symtab;
+        if (xx.m_type->type == ASR::ttypeType::SymbolicExpression) {
+            SymbolTable* module_scope = current_scope->parent;
+            symbolic_replaces_with_CPtr_Function = true;
+            std::string var_name = xx.m_name;
+            std::string placeholder = "_" + std::string(var_name);
+
+            // defining CPtr variable
+            ASR::ttype_t *type1 = ASRUtils::TYPE(ASR::make_CPtr_t(al, xx.base.base.loc));
+            xx.m_type = type1;
+
+            ASR::ttype_t *type2 = ASRUtils::TYPE(ASR::make_Integer_t(al, xx.base.base.loc, 8));
+            ASR::symbol_t* sym2 = ASR::down_cast<ASR::symbol_t>(
+                ASR::make_Variable_t(al, xx.base.base.loc, current_scope,
+                                    s2c(al, placeholder), nullptr, 0,
+                                    xx.m_intent, nullptr,
+                                    nullptr, xx.m_storage,
+                                    type2, nullptr, xx.m_abi,
+                                    xx.m_access, xx.m_presence,
+                                    xx.m_value_attr));
+
+            current_scope->add_symbol(s2c(al, placeholder), sym2);
+
+            std::string new_name = "basic_new_stack";
+            if (!module_scope->get_symbol(new_name)) {
+                std::string header = "symengine/cwrapper.h";
+                SymbolTable *fn_symtab = al.make_new<SymbolTable>(module_scope);
+
+                Vec<ASR::expr_t*> args;
+                {
+                    args.reserve(al, 1);
+                    ASR::symbol_t *arg = ASR::down_cast<ASR::symbol_t>(ASR::make_Variable_t(
+                        al, xx.base.base.loc, fn_symtab, s2c(al, "x"), nullptr, 0, ASR::intentType::In,
+                        nullptr, nullptr, ASR::storage_typeType::Default, type1, nullptr,
+                        ASR::abiType::BindC, ASR::Public, ASR::presenceType::Required, true));
+                    fn_symtab->add_symbol(s2c(al, "x"), arg);
+                    args.push_back(al, ASRUtils::EXPR(ASR::make_Var_t(al, xx.base.base.loc, arg)));
+                }
+
+                Vec<ASR::stmt_t*> body;
+                body.reserve(al, 1);
+
+                Vec<char *> dep;
+                dep.reserve(al, 1);
+
+                ASR::asr_t* new_subrout = ASRUtils::make_Function_t_util(al, xx.base.base.loc,
+                    fn_symtab, s2c(al, new_name), dep.p, dep.n, args.p, args.n, body.p, body.n,
+                    nullptr, ASR::abiType::BindC, ASR::accessType::Public,
+                    ASR::deftypeType::Interface, s2c(al, new_name), false, false, false,
+                    false, false, nullptr, 0, false, false, false, s2c(al, header));
+                ASR::symbol_t *new_symbol = ASR::down_cast<ASR::symbol_t>(new_subrout);
+                module_scope->add_symbol(new_name, new_symbol);
+            }
+
+            ASR::symbol_t* var_sym = current_scope->get_symbol(var_name);
+            ASR::symbol_t* placeholder_sym = current_scope->get_symbol(placeholder);
+            ASR::expr_t* target1 = ASRUtils::EXPR(ASR::make_Var_t(al, xx.base.base.loc, placeholder_sym));
+            ASR::expr_t* target2 = ASRUtils::EXPR(ASR::make_Var_t(al, xx.base.base.loc, var_sym));
+
+            // statement 1
+            ASR::expr_t* value1 = ASRUtils::EXPR(ASR::make_Cast_t(al, xx.base.base.loc,
+                ASRUtils::EXPR(ASR::make_IntegerConstant_t(al, xx.base.base.loc, 0,
+                ASRUtils::TYPE(ASR::make_Integer_t(al, xx.base.base.loc, 4)))),
+                (ASR::cast_kindType)ASR::cast_kindType::IntegerToInteger, type2,
+                ASRUtils::EXPR(ASR::make_IntegerConstant_t(al, xx.base.base.loc, 0, type2))));
+
+            // statement 2
+            ASR::expr_t* value2 = ASRUtils::EXPR(ASR::make_PointerNullConstant_t(al, xx.base.base.loc, type1));
+
+            // statement 3
+            ASR::expr_t* get_pointer_node = ASRUtils::EXPR(ASR::make_GetPointer_t(al, xx.base.base.loc,
+                target1, ASRUtils::TYPE(ASR::make_Pointer_t(al, xx.base.base.loc, type2)), nullptr));
+            ASR::expr_t* value3 = ASRUtils::EXPR(ASR::make_PointerToCPtr_t(al, xx.base.base.loc, get_pointer_node,
+                type1, nullptr));
+
+            // statement 4
+            ASR::symbol_t* basic_new_stack_sym = module_scope->get_symbol(new_name);
+            Vec<ASR::call_arg_t> call_args;
+            call_args.reserve(al, 1);
+            ASR::call_arg_t call_arg;
+            call_arg.loc = xx.base.base.loc;
+            call_arg.m_value = target2;
+            call_args.push_back(al, call_arg);
+
+            // defining the assignment statement
+            ASR::stmt_t* stmt1 = ASRUtils::STMT(ASR::make_Assignment_t(al, xx.base.base.loc, target1, value1, nullptr));
+            ASR::stmt_t* stmt2 = ASRUtils::STMT(ASR::make_Assignment_t(al, xx.base.base.loc, target2, value2, nullptr));
+            ASR::stmt_t* stmt3 = ASRUtils::STMT(ASR::make_Assignment_t(al, xx.base.base.loc, target2, value3, nullptr));
+            ASR::stmt_t* stmt4 = ASRUtils::STMT(ASR::make_SubroutineCall_t(al, xx.base.base.loc, basic_new_stack_sym,
+                basic_new_stack_sym, call_args.p, call_args.n, nullptr));
+
+            pass_result.push_back(al, stmt1);
+            pass_result.push_back(al, stmt2);
+            pass_result.push_back(al, stmt3);
+            pass_result.push_back(al, stmt4);
+        }
+        current_scope = current_scope_copy;
+    }
+};
+
+void pass_replace_symbolic(Allocator &al, ASR::TranslationUnit_t &unit,
+                            const LCompilers::PassOptions& /*pass_options*/) {
+    ReplaceSymbolicVisitor v(al);
+    v.visit_TranslationUnit(unit);
+}
+} // namespace LCompilers

src/libasr/pass/replace_symbolic.h

@@ -0,0 +1,14 @@
+#ifndef LIBASR_PASS_REPLACE_SYMBOLIC_H
+#define LIBASR_PASS_REPLACE_SYMBOLIC_H
+
+#include <libasr/asr.h>
+#include <libasr/utils.h>
+
+namespace LCompilers {
+
+    void pass_replace_symbolic(Allocator &al, ASR::TranslationUnit_t &unit,
+                                const PassOptions &pass_options);
+
+} // namespace LCompilers
+
+#endif // LIBASR_PASS_REPLACE_SYMBOLIC_H