From 1277369f06388846f99d22d1ecc6b117d3f18dfa Mon Sep 17 00:00:00 2001
From: Nicolas Kruse <nicolas@nonan.net>
Date: Mon, 20 Oct 2025 22:23:31 +0200
Subject: [PATCH] fast c pow function integrated including unit test

---
 src/copapy/_target.py      |  6 +++---
 tests/test_ext_ops.py      | 31 +++++++++++++++++++++++++++++++
 tools/crosscompile.sh      |  2 +-
 tools/generate_stencils.py | 18 +++++++++++++++++-
 4 files changed, 52 insertions(+), 5 deletions(-)
 create mode 100644 tests/test_ext_ops.py

diff --git a/src/copapy/_target.py b/src/copapy/_target.py
index 631cb70..9f77903 100644
--- a/src/copapy/_target.py
+++ b/src/copapy/_target.py
@@ -1,4 +1,4 @@
-from typing import overload
+from typing import Iterable, overload
 from . import _binwrite as binw
 from coparun_module import coparun, read_data_mem
 import struct
@@ -20,10 +20,10 @@ class Target():
         self.sdb = stencil_db_from_package(arch, optimization)
         self._variables: dict[Net, tuple[int, int, str]] = dict()
 
-    def compile(self, *variables: int | float | cpint | cpfloat | cpbool | list[int | float | cpint | cpfloat | cpbool]) -> None:
+    def compile(self, *variables: int | float | cpint | cpfloat | cpbool | Iterable[int | float | cpint | cpfloat | cpbool]) -> None:
         nodes: list[Node] = []
         for s in variables:
-            if isinstance(s, list):
+            if isinstance(s, Iterable):
                 for net in s:
                     assert isinstance(net, Net), f"The folowing element is not a Net: {net}"
                     nodes.append(Write(net))
diff --git a/tests/test_ext_ops.py b/tests/test_ext_ops.py
new file mode 100644
index 0000000..8123694
--- /dev/null
+++ b/tests/test_ext_ops.py
@@ -0,0 +1,31 @@
+from copapy import cpvalue, Target
+import pytest
+import copapy
+
+
+def test_compile():
+    c_i = cpvalue(9)
+    c_f = cpvalue(1.111)
+    # c_b = cpvalue(True)
+
+    ret_test = (c_f ** c_f, c_i ** c_i)
+    ret_ref = (1.111 ** 1.111, 9 ** 9)
+
+    tg = Target()
+    print('* compile and copy ...')
+    tg.compile(ret_test)
+    print('* run and copy ...')
+    tg.run()
+    print('* finished')
+
+    for test, ref in zip(ret_test, ret_ref):
+        assert isinstance(test, copapy.CPNumber)
+        val = tg.read_value(test)
+        print('+', val, ref, type(val), test.dtype)
+        #for t in (int, float, bool):
+        #    assert isinstance(val, t) == isinstance(ref, t), f"Result type does not match for {val} and {ref}"
+        assert val == pytest.approx(ref, 1e-3), f"Result does not match: {val} and reference: {ref}"  # pyright: ignore[reportUnknownMemberType]
+
+
+if __name__ == "__main__":
+    test_compile()
diff --git a/tools/crosscompile.sh b/tools/crosscompile.sh
index 684045d..d81b3e8 100644
--- a/tools/crosscompile.sh
+++ b/tools/crosscompile.sh
@@ -47,7 +47,7 @@ mips-linux-gnu-gcc-13 -$OPT -c $SRC -o $DEST/stencils_mips_$OPT.o
 mipsel-linux-gnu-gcc-13 -$OPT -c $SRC -o $DEST/stencils_mipsel_$OPT.o
 
 # RISCV 32 Bit
-riscv64-linux-gnu-gcc-13 -$OPT -march=rv32imac -mabi=ilp32 -c $SRC -o $DEST/stencils_riscv32_$OPT.o
+# riscv64-linux-gnu-gcc-13 -$OPT -march=rv32imac -mabi=ilp32 -c $SRC -o $DEST/stencils_riscv32_$OPT.o
 
 # RISCV 64 Bit
 riscv64-linux-gnu-gcc-13 -$OPT -c $SRC -o $DEST/stencils_riscv64_$OPT.o
diff --git a/tools/generate_stencils.py b/tools/generate_stencils.py
index 93bc081..f81eb32 100644
--- a/tools/generate_stencils.py
+++ b/tools/generate_stencils.py
@@ -26,6 +26,19 @@ def get_aux_funcs() -> str:
         if (x < 0 && x != (float)i) i -= 1;
         return i;
     }
+
+    float fast_pow_float(float base, float exponent) {
+        union {
+            float f;
+            uint32_t i;
+        } u;
+
+        u.f = base;
+        int32_t x = u.i;
+        int32_t y = (int32_t)(exponent * (x - 1072632447) + 1072632447);
+        u.i = (uint32_t)y;
+        return u.f;
+    }
     """
 
 
@@ -64,7 +77,8 @@ def get_op_code_float(op: str, type1: str, type2: str) -> str:
 def get_pow(type1: str, type2: str) -> str:
     return f"""
     {stencil_func_prefix}void pow_{type1}_{type2}({type1} arg1, {type2} arg2) {{
-        result_float_{type2}((float)math_pow((double)arg1, (double)arg2), arg2);
+        //result_float_{type2}((float)math_pow((double)arg1, (double)arg2), arg2);
+        result_float_{type2}(fast_pow_float((float)arg1, (float)arg2), arg2);
     }}
     """
 
@@ -144,6 +158,8 @@ if __name__ == "__main__":
     // Auto-generated stencils for copapy
     // Do not edit manually
 
+    #include <stdint.h>
+
     double (*math_pow)(double, double);
 
     volatile int dummy_int = 1337;