Bring back target print function.

artiq/compiler/prelude.py

@@ -47,4 +47,5 @@ def globals():
 
         # ARTIQ utility functions
         "rtio_log":             builtins.fn_rtio_log(),
+        "core_log":             builtins.fn_print(),
     }

artiq/compiler/targets.py

@@ -73,6 +73,7 @@ class Target:
     triple = "unknown"
     data_layout = ""
     features = []
+    print_function = "printf"
 
 
     def __init__(self):
@@ -195,3 +196,4 @@ class OR1KTarget(Target):
     triple = "or1k-linux"
     data_layout = "E-m:e-p:32:32-i64:32-f64:32-v64:32-v128:32-a:0:32-n32"
     features = ["mul", "div", "ffl1", "cmov", "addc"]
+    print_function = "core_log"

artiq/compiler/transforms/llvm_ir_generator.py

@@ -358,7 +358,7 @@ class LLVMIRGenerator:
             llty = ll.FunctionType(llptr, [])
         elif name == "llvm.stackrestore":
             llty = ll.FunctionType(llvoid, [llptr])
-        elif name == "printf":
+        elif name == self.target.print_function:
             llty = ll.FunctionType(llvoid, [llptr], var_arg=True)
         elif name == "rtio_log":
             llty = ll.FunctionType(llvoid, [lli64, llptr], var_arg=True)
@@ -904,7 +904,8 @@ class LLVMIRGenerator:
         elif insn.op in ("printf", "rtio_log"):
             # We only get integers, floats, pointers and strings here.
             llargs = map(self.map, insn.operands)
-            return self.llbuilder.call(self.llbuiltin(insn.op), llargs,
+            func_name = self.target.print_function if insn.op == "printf" else insn.op
+            return self.llbuilder.call(self.llbuiltin(func_name), llargs,
                                        name=insn.name)
         elif insn.op == "exncast":
             # This is an identity cast at LLVM IR level.

artiq/runtime/ksupport.c

@@ -97,6 +97,8 @@ static const struct symbol runtime_exports[] = {
     {"abort", &ksupport_abort},
 
     /* proxified syscalls */
+    {"core_log", &core_log},
+
     {"now", &now},
 
     {"watchdog_set", &watchdog_set},