Implement sum()

build.sh

@@ -9,3 +9,8 @@ python grammar/asdl_py.py
 # Generate a parse tree from fortran.g4
 antlr4="java org.antlr.v4.Tool"
 (cd grammar; $antlr4 -Dlanguage=Python3 -no-listener -visitor fortran.g4 -o ../liblfort/parser)
+
+# Compile LFort runtime library
+CFLAGS="-Wall -g"
+gcc $CFLAGS -o lfort_intrinsics.o -c lfort_intrinsics.c
+ar rcs liblfort.a lfort_intrinsics.o

lfort_intrinsics.c

@@ -0,0 +1,9 @@
+double _lfort_sum(int n, double *v)
+{
+    int i, r;
+    r = 0;
+    for (i=0; i < n; i++) {
+        r += v[i];
+    }
+    return r;
+}

liblfort/codegen/gen.py

@@ -137,6 +137,7 @@ def visit_Program(self, node):
         self.builder = ir.IRBuilder(block)
 
         for ssym in self.symbol_table:
+            if ssym in ["abs", "sqrt", "log", "sum"]: continue
             sym = self.symbol_table[ssym]
             type_f = sym["type"]
             if isinstance(type_f, Array):
@@ -155,6 +156,10 @@ def visit_Program(self, node):
                 'llvm.sqrt', [ir.DoubleType()])
         self.symbol_table["log"]["fn"] = self.module.declare_intrinsic(
                 'llvm.log', [ir.DoubleType()])
+        fn_type = ir.FunctionType(ir.DoubleType(),
+                [ir.IntType(64), ir.DoubleType().as_pointer()])
+        fn_sum = ir.Function(self.module, fn_type, name="_lfort_sum")
+        self.symbol_table["sum"]["fn"] = fn_sum
 
         self.visit_sequence(node.contains)
         self.visit_sequence(node.body)
@@ -276,7 +281,17 @@ def visit_FuncCallOrArray(self, node):
             sym = self.symbol_table[node.func]
             fn = sym["fn"]
             arg = self.visit(node.args[0])
-            return self.builder.call(fn, [arg])
+            if sym["name"] == "sum":
+                # FIXME: for now we assume an array was passed in:
+                arg = self.symbol_table[node.args[0].id]
+                addr = self.builder.gep(arg["ptr"],
+                        [ir.Constant(ir.IntType(64), 0),
+                         ir.Constant(ir.IntType(64), 0)])
+                # FIXME: pass in the length of the array
+                return self.builder.call(fn, [ir.Constant(ir.IntType(64), 3),
+                    addr])
+            else:
+                return self.builder.call(fn, [arg])
 
     def visit_If(self, node):
         cond = self.visit(node.test)

liblfort/liblfort.py

@@ -130,6 +130,6 @@ def main():
         os.system("ld -o %s %s %s" % (outfile, objfile, LDFLAGS))
     else:
         # Invoke a C compiler to do the linking
-        os.system("cc -o %s %s -lm" % (outfile, objfile))
+        os.system("cc -o %s %s -L. -llfort -lm" % (outfile, objfile))
     if objfile == "tmp_object_file.o":
         os.system("rm %s" % objfile)

liblfort/semantic/analyze.py

@@ -85,6 +85,7 @@ def __init__(self):
                 "abs": {"name": "abs", "type": Real()},
                 "sqrt": {"name": "sqrt", "type": Real()},
                 "log": {"name": "log", "type": Real()},
+                "sum": {"name": "sum", "type": Real()},
                 }
 
     def visit_Declaration(self, node):

tests/arrays_02.f90

@@ -1,8 +1,10 @@
 program arrays_02
 implicit none
 integer, parameter :: dp
-real(dp) :: a(3)
+real(dp) :: a(3), b
 a(1) = 3._dp
 a(2) = 2._dp
 a(3) = 1._dp
+b = sum(a)
+if (abs(b-6._dp) > 1e-12_dp) error stop
 end