From 1536ea0bbb31234b87b50f9b3c11d3cf6649b7f5 Mon Sep 17 00:00:00 2001
From: "Johan B.W. de Vries" <info@jbwdevries.nl>
Date: Fri, 10 Nov 2023 14:53:48 +0100
Subject: [PATCH] Enable use of bytes in constants

Including using them in tuple constants.
---
 phasm/codestyle.py                        |  3 +++
 phasm/compiler.py                         | 18 ++++++++++++++----
 phasm/ourlang.py                          |  3 +++
 tests/integration/test_lang/test_bytes.py | 14 ++++++++++++++
 tests/integration/test_lang/test_tuple.py | 20 ++++++++++++++++++++
 5 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/phasm/codestyle.py b/phasm/codestyle.py
index c984937..ea5c207 100644
--- a/phasm/codestyle.py
+++ b/phasm/codestyle.py
@@ -68,6 +68,9 @@ def expression(inp: ourlang.Expression) -> str:
         # could not fit in the given float type
         return str(inp.value)
 
+    if isinstance(inp, ourlang.ConstantBytes):
+        return repr(inp.value)
+
     if isinstance(inp, ourlang.ConstantTuple):
         return '(' + ', '.join(
             expression(x)
diff --git a/phasm/compiler.py b/phasm/compiler.py
index b7f45fa..b4ebd20 100644
--- a/phasm/compiler.py
+++ b/phasm/compiler.py
@@ -22,6 +22,8 @@ LOAD_STORE_TYPE_MAP = {
     'u64': 'i64',
     'f32': 'f32',
     'f64': 'f64',
+
+    'bytes': 'i32', # Bytes are passed around as pointers
 }
 
 def phasm_compile(inp: ourlang.Module) -> wasm.Module:
@@ -237,7 +239,6 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         raise NotImplementedError(f'Constants with type {inp.type3:s}')
 
     if isinstance(inp, ourlang.ConstantBytes):
-        assert inp.data_block is not None, 'Bytes must be memory stored'
         assert inp.data_block.address is not None, 'Value not allocated'
         wgn.i32.const(inp.data_block.address)
         return
@@ -742,9 +743,18 @@ def module_data(inp: ourlang.ModuleData) -> bytes:
                 continue
 
             if constant.type3 == type3types.bytes:
-                assert isinstance(constant.value, bytes)
-                data_list.append(module_data_u32(len(constant.value)))
-                data_list.append(constant.value)
+                assert isinstance(constant, ourlang.ConstantBytes)
+
+                if block is not constant.data_block:
+                    # It's stored in a different block
+                    # We only need to store its address
+                    # This happens for example when a tuple refers
+                    # to a bytes constant
+                    assert constant.data_block.address is not None
+                    data_list.append(module_data_u32(constant.data_block.address))
+                else:
+                    data_list.append(module_data_u32(len(constant.value)))
+                    data_list.append(constant.value)
                 continue
 
             raise NotImplementedError(constant, constant.type3, constant.value)
diff --git a/phasm/ourlang.py b/phasm/ourlang.py
index 9561590..d3ca565 100644
--- a/phasm/ourlang.py
+++ b/phasm/ourlang.py
@@ -62,6 +62,9 @@ class ConstantBytes(Constant):
         self.data_block = data_block
 
     def __repr__(self) -> str:
+        # Do not repr the whole ModuleDataBlock
+        # As this has a reference back to this constant for its data
+        # which it needs to compile the data into the program
         return f'ConstantBytes({repr(self.value)}, @{repr(self.data_block.address)})'
 
 class ConstantTuple(Constant):
diff --git a/tests/integration/test_lang/test_bytes.py b/tests/integration/test_lang/test_bytes.py
index af3f78d..6a3fe07 100644
--- a/tests/integration/test_lang/test_bytes.py
+++ b/tests/integration/test_lang/test_bytes.py
@@ -42,6 +42,20 @@ def testEntry(f: bytes) -> u8:
 
     assert 0x61 == result.returned_value
 
+@pytest.mark.integration_test
+def test_constant():
+    code_py = """
+CONSTANT: bytes = b'ABCDEF'
+
+@exported
+def testEntry() -> u8:
+    return CONSTANT[0]
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert 0x41 == result.returned_value
+
 @pytest.mark.integration_test
 def test_bytes_index_out_of_bounds():
     code_py = """
diff --git a/tests/integration/test_lang/test_tuple.py b/tests/integration/test_lang/test_tuple.py
index bf8033d..21bb86e 100644
--- a/tests/integration/test_lang/test_tuple.py
+++ b/tests/integration/test_lang/test_tuple.py
@@ -119,6 +119,26 @@ def testEntry() -> u64:
 
     assert 128 == result.returned_value
 
+@pytest.mark.integration_test
+def test_bytes_as_part_of_tuple():
+    code_py = """
+CONSTANT: (bytes, u64, ) = (b'ABCDEF', 19, )
+
+def l0(c: bytes) -> u8:
+    return c[0]
+
+def l1(c: (bytes, u64, )) -> u8:
+    return l0(c[0])
+
+@exported
+def testEntry() -> u8:
+    return l1(CONSTANT)
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert 0x41 == result.returned_value
+
 @pytest.mark.integration_test
 def test_function_call_element_type_mismatch():
     code_py = """