add support for non-FPU/UBC/MMU/cache SH4 instructions

Previously, ast transformations were performed informally as ad-hoc
modifications to the generated C source code. In this commit, the
same transformations are performed by rewriting the ast prior to code
generation time.

The most significant new transformer is transform_assignment_list.
This transforms assignments such as:

  a, b, c = f(b, c, d)

To:

  a = f(&b, &c, d)

The former syntax is used frequently in the manual's description of
FPU-related instructions.

ast_to_c_source.py

@@ -0,0 +1,285 @@
+from dataclasses import dataclass
+
+from parser import Tree
+from lexer import Identifier, Punctuator, IntegerConstant
+import identifier_substitution
+
+def argument_list(tree):
+    yield from generate(tree.children[0])
+    yield ", "
+    yield from generate(tree.children[1])
+
+def _is_new_temporary(tree):
+    return (
+        type(tree) is Identifier
+        and tree.token not in identifier_substitution.mapping
+        and tree.token not in ctx.identifiers
+    )
+
+def assignment_list(tree):
+    yield from generate(tree.children[0])
+    yield ", "
+    yield from generate(tree.children[1])
+
+def assignment(tree):
+    yield from generate(tree.children[0])
+    yield " = "
+    yield from generate(tree.children[1])
+
+def bit_extraction(tree):
+    yield "bit_extract("
+    yield from generate(tree.children[0])
+    yield ", "
+    yield from generate(tree.children[1])
+    yield ")"
+
+def bitwise_and(tree):
+    yield from generate(tree.children[0])
+    yield " & "
+    yield from generate(tree.children[1])
+
+def bitwise_or(tree):
+    yield from generate(tree.children[0])
+    yield " | "
+    yield from generate(tree.children[1])
+
+def bitwise_xor(tree):
+    yield from generate(tree.children[0])
+    yield " ^ "
+    yield from generate(tree.children[1])
+
+def block_item_list(tree):
+    yield from generate(tree.children[0])
+    yield from generate(tree.children[1])
+
+def compound_statement(tree):
+    yield "\n{\n"
+    if tree.children:
+        yield from generate(tree.children[0])
+    yield "}\n"
+
+def expression_statement(tree):
+    yield from generate(tree.children[0])
+    yield ";\n"
+
+def for_expression(tree):
+    yield from generate(tree.children[0])
+    yield ", "
+    if len(tree.children) > 1:
+        yield from generate(tree.children[1])
+    else:
+        yield "1"
+
+def function_call(tree):
+    assert len(tree.children) in {1, 2}
+    yield from generate(tree.children[0])
+    yield "("
+    if len(tree.children) == 2:
+        yield from generate(tree.children[1])
+    yield ")"
+
+def grouping(tree):
+    yield "("
+    yield from generate(tree.children[0])
+    yield ")"
+
+def _if(tree):
+    yield "if ("
+    yield from generate(tree.children[0])
+    yield ") "
+    yield from generate(tree.children[1])
+
+def if_else(tree):
+    yield "if ("
+    yield from generate(tree.children[0])
+    yield ") "
+    yield from generate(tree.children[1])
+    yield "else "
+    yield from generate(tree.children[2])
+
+def logical_and(tree):
+    yield from generate(tree.children[0])
+    yield " && "
+    yield from generate(tree.children[1])
+
+def logical_or(tree):
+    yield from generate(tree.children[0])
+    yield " || "
+    yield from generate(tree.children[1])
+
+def member(tree):
+    yield from generate(tree.children[0])
+    yield "."
+    yield from generate(tree.children[1])
+
+def subscript(tree):
+    yield from generate(tree.children[0])
+    yield "["
+    yield from generate(tree.children[1])
+    yield "]"
+
+def throw(tree):
+    yield "return "
+    yield from generate(tree.children[0])
+    yield "(state);\n"
+
+def throw_arg(tree):
+    yield "return "
+    yield from generate(tree.children[0])
+    yield "(state, "
+    yield from generate(tree.children[1])
+    yield ");\n"
+
+def unary_complement(tree):
+    yield from "~"
+    yield from generate(tree.children[0])
+
+def unary_int(tree):
+    yield "unary_int("
+    yield from generate(tree.children[0])
+    yield ")"
+
+def unary_negation(tree):
+    yield "-"
+    yield from generate(tree.children[0])
+
+def unary_not(tree):
+    yield "!"
+    yield from generate(tree.children[0])
+
+#
+def addition(tree):
+    yield from generate(tree.children[0])
+    yield " + "
+    yield from generate(tree.children[1])
+
+def division(tree):
+    yield from generate(tree.children[0])
+    yield " / "
+    yield from generate(tree.children[1])
+
+def equality_equal(tree):
+    yield from generate(tree.children[0])
+    yield " == "
+    yield from generate(tree.children[1])
+
+def equality_not_equal(tree):
+    yield from generate(tree.children[0])
+    yield " != "
+    yield from generate(tree.children[1])
+
+def greater_than(tree):
+    yield from generate(tree.children[0])
+    yield " > "
+    yield from generate(tree.children[1])
+
+def greater_than_equal(tree):
+    yield from generate(tree.children[0])
+    yield " >= "
+    yield from generate(tree.children[1])
+
+def left_shift(tree):
+    yield from generate(tree.children[0])
+    # hack for left shift by LHS constant
+    if type(tree.children[0]) is IntegerConstant:
+        yield "LL"
+    yield " << "
+    yield from generate(tree.children[1])
+
+def less_than(tree):
+    yield from generate(tree.children[0])
+    yield " < "
+    yield from generate(tree.children[1])
+
+def less_than_equal(tree):
+    yield from generate(tree.children[0])
+    yield " <= "
+    yield from generate(tree.children[1])
+
+def multiplication(tree):
+    yield from generate(tree.children[0])
+    yield " * "
+    yield from generate(tree.children[1])
+
+def right_shift(tree):
+    yield from generate(tree.children[0])
+    yield " >> "
+    yield from generate(tree.children[1])
+
+def subtraction(tree):
+    yield from generate(tree.children[0])
+    yield " - "
+    yield from generate(tree.children[1])
+
+def declaration(tree):
+    assert len(tree.children) >= 2, tree
+    yield from generate(tree.children[0])
+    yield " "
+    for child in tree.children[1:-1]:
+        yield from generate(child)
+        yield ", "
+    yield from generate(tree.children[-1])
+
+def unary_reference(tree):
+    yield "&"
+    assert len(tree.children) == 1
+    yield from generate(tree.children[0])
+
+def identifier(token):
+    yield token.token
+
+def constant(elem):
+    yield elem.token.lower()
+
+def generate(elem):
+    mapping = {
+        "argument_list": argument_list,
+        "assignment_list": assignment_list,
+        "assignment": assignment,
+        "bit_extraction": bit_extraction,
+        "bitwise_and": bitwise_and,
+        "bitwise_or": bitwise_or,
+        "bitwise_xor": bitwise_xor,
+        "block_item_list": block_item_list,
+        "compound_statement": compound_statement,
+        "expression_statement": expression_statement,
+        "for_expression": for_expression,
+        "function_call": function_call,
+        "grouping": grouping,
+        "if": _if,
+        "if_else": if_else,
+        "logical_and": logical_and,
+        "logical_or": logical_or,
+        "member": member,
+        "subscript": subscript,
+        "throw": throw,
+        "throw_arg": throw_arg,
+        "unary_complement": unary_complement,
+        "unary_int": unary_int,
+        "unary_negation": unary_negation,
+        "unary_not": unary_not,
+        #
+        "addition": addition,
+        "division": division,
+        "equality_equal": equality_equal,
+        "equality_not_equal": equality_not_equal,
+        "greater_than": greater_than,
+        "greater_than_equal": greater_than_equal,
+        "left_shift": left_shift,
+        "less_than": less_than,
+        "less_than_equal": less_than_equal,
+        "multiplication": multiplication,
+        "right_shift": right_shift,
+        "subtraction": subtraction,
+        #
+        "declaration": declaration,
+        "unary_reference": unary_reference,
+    }
+    if type(elem) is Tree:
+        yield from mapping[elem.operation](elem)
+    elif type(elem) is Identifier:
+        yield from identifier(elem)
+    elif type(elem) is IntegerConstant:
+        yield from constant(elem)
+    else:
+        assert False, type(elem)

ast_transformers.py

@@ -0,0 +1,194 @@
+from pprint import pprint
+
+from parser import Tree
+from lexer import Identifier, Punctuator, IntegerConstant
+
+import identifier_substitution
+
+def find_locals__walk_assignment_lhs(tree):
+    if type(tree) is Tree:
+        for child in tree.children:
+            yield from find_locals__walk_assignment_lhs(child)
+    elif type(tree) is Identifier:
+        token = tree
+        if token.token not in {'m', 'n', 'i', 'd'}:
+            if token.token.lower() == token.token:
+                assert token.token not in identifier_substitution.mapping, token.token
+                yield token.token
+
+def find_locals__walk_assignment(tree):
+    if type(tree) is Tree:
+        if tree.operation == "assignment":
+            yield from find_locals__walk_assignment_lhs(tree.children[0])
+            for child in tree.children[1:]:
+                yield from find_locals__walk_assignment(child)
+        else:
+            for child in tree.children:
+                yield from find_locals__walk_assignment(child)
+
+def transform_assignment_list__collect_identifiers(tree, operation):
+    if type(tree) == Tree:
+        assert tree.operation == operation, pprint(tree)
+        for child in tree.children:
+            yield from transform_assignment_list__collect_identifiers(child, operation)
+    elif type(tree) == Identifier:
+        yield tree.token
+
+def transform_assignment_list__assignment(tree):
+    assert tree.operation == "assignment", tree
+    # first, collect the lhs
+    if type(tree.children[0]) is not Tree or tree.children[0].operation != 'assignment_list':
+        return tree
+
+    lhs = transform_assignment_list__collect_identifiers(tree.children[0], "assignment_list")
+
+    assert tree.children[1].operation == "function_call", (tree.children[1].operation, pprint(tree))
+    function_call = tree.children[1]
+    rhs = list(transform_assignment_list__collect_identifiers(function_call.children[1], "argument_list"))
+
+    common = []
+    lhs_only = []
+    for l_token in lhs:
+        if l_token in rhs:
+            common.append(l_token)
+        else:
+            lhs_only.append(l_token)
+
+    def gen_argument_list(tree):
+        if type(tree) is Tree:
+            assert tree.operation == 'argument_list'
+            return Tree(
+                operation=tree.operation,
+                children=[gen_argument_list(child) for child in tree.children]
+            )
+        elif type(tree) is Identifier:
+            if tree.token in common:
+                return Tree(
+                    operation="unary_reference",
+                    children=[tree]
+                )
+            else:
+                return tree
+        else:
+            return tree
+
+    def gen_function_call():
+        return Tree(
+            operation="function_call",
+            children=[
+                function_call.children[0],
+                gen_argument_list(function_call.children[1]),
+            ]
+        )
+
+    if len(lhs_only) == 0:
+        return gen_function_call()
+    elif len(lhs_only) == 1:
+        return Tree(
+            operation="assignment",
+            children=[Identifier(line=-1, token=lhs_only[0]), gen_function_call()]
+        )
+    else:
+        assert False, (lhs_only, common, pprint(tree))
+
+def transform_assignment_list(tree):
+    if type(tree) is Tree:
+        if tree.operation == "assignment":
+            return transform_assignment_list__assignment(tree)
+        else:
+            return Tree(
+                operation=tree.operation,
+                children=[
+                    transform_assignment_list(child)
+                    for child in tree.children
+                ]
+            )
+    else:
+        return tree
+
+def transform_local_declarations(statements):
+    all_locals = []
+    for statement in statements:
+        all_locals.extend(find_locals__walk_assignment(statement))
+
+    set_locals = []
+    for local in all_locals:
+        if not any(s.token == local for s in set_locals):
+            set_locals.append(Identifier(line=-1, token=local))
+
+    if set_locals:
+        yield Tree(operation="expression_statement",
+                   children=[Tree(operation="declaration",
+                                  children=[Identifier(line=-1, token="int64_t"), *set_locals])])
+
+def transform_identifiers(tree):
+    if type(tree) is Tree:
+        return Tree(
+            operation=tree.operation,
+            children=[transform_identifiers(child) for child in tree.children]
+        )
+    elif type(tree) is Identifier:
+        token = tree
+        if token.token in identifier_substitution.mapping:
+            return Identifier(
+                line=token.line,
+                token=identifier_substitution.mapping[token.token]
+            )
+        else:
+            return token
+    else:
+        return tree
+
+require_extra_arguments = {
+    "IsDelaySlot": "state",
+    "SLEEP": "state",
+    "OCBP" : "state",
+    "WriteMemory8" : "map",
+    "WriteMemory16": "map",
+    "WriteMemory32": "map",
+    "ReadMemory8"  : "map",
+    "ReadMemory16" : "map",
+    "ReadMemory32" : "map",
+}
+
+def transform_function_arguments(tree):
+    def arguments(arg):
+        identifier = Identifier(line=tree.children[0].line, token=arg)
+        if len(tree.children) == 1:
+            return identifier
+        else:
+            assert len(tree.children) == 2, tree
+            return Tree(
+                operation='argument_list',
+                children=[
+                    identifier,
+                    transform_function_arguments(tree.children[1])
+                ]
+            )
+
+    if type(tree) is Tree:
+        if tree.operation == "function_call":
+            assert type(tree.children[0]) is Identifier
+            if tree.children[0].token in require_extra_arguments:
+                return Tree(
+                    operation=tree.operation,
+                    children=[
+                        tree.children[0],
+                        arguments(require_extra_arguments[tree.children[0].token])
+                    ]
+                )
+        return Tree(
+            operation=tree.operation,
+            children=[transform_function_arguments(child) for child in tree.children]
+        )
+    else:
+        return tree
+
+def transform_statements(statements):
+    yield from transform_local_declarations(statements)
+
+    for statement in statements:
+        statement = transform_assignment_list(statement)
+        statement = transform_function_arguments(statement)
+        statement = transform_identifiers(statement)
+        yield statement

bitfield.py

@@ -1,74 +0,0 @@
-sr_bits = (
-    ("T"    , 0 , 1),   # true/false condition
-    ("S"    , 1 , 1),   # saturation
-    ("IMASK", 4 , 4),   # interrupt mask level, 4 bits
-    ("Q"    , 8 , 1),   # state for divide step
-    ("M"    , 9 , 1),   # state for divide step
-    ("FD"   , 15, 1),  # FPU disable
-    ("BL"   , 28, 1),  # Exception/interrupt block bit
-    ("RB"   , 29, 1),  # General register bank specifier in privileged mode
-    ("MD"   , 30, 1),  # Processor mode
-)
-
-#define FPSCR__RM                      (1 << 0 ) /* Rounding mode */
-#define FPSCR__FLAG_INEXACT            (1 << 2 )
-#define FPSCR__FLAG_UNDERFLOW          (1 << 3 )
-#define FPSCR__FLAG_OVERFLOW           (1 << 4 )
-#define FPSCR__FLAG_DIVISION_BY_ZERO   (1 << 5 )
-#define FPSCR__FLAG_INVALID_OPERATION  (1 << 6 )
-#define FPSCR__ENABLE_INEXACT          (1 << 7 )
-#define FPSCR__ENABLE_UNDERFLOW        (1 << 8 )
-#define FPSCR__ENABLE_OVERFLOW         (1 << 9 )
-#define FPSCR__ENABLE_DIVISION_BY_ZERO (1 << 10)
-#define FPSCR__ENABLE_INVALID          (1 << 11)
-#define FPSCR__CAUSE_INEXACT           (1 << 12)
-#define FPSCR__CAUSE_UNDERFLOW         (1 << 13)
-#define FPSCR__CAUSE_OVERFLOW          (1 << 14)
-#define FPSCR__CAUSE_DIVISION_BY_ZERO  (1 << 15)
-#define FPSCR__CAUSE_INVALID           (1 << 16)
-#define FPSCR__CAUSE_FPU_ERROR         (1 << 17)
-#define FPSCR__DN                      (1 << 18) /* Denormalization mode */
-#define FPSCR__PR                      (1 << 19) /* Precision mode */
-#define FPSCR__SZ                      (1 << 20) /* Transfer size mode */
-#define FPSCR__FR                      (1 << 21) /* Floating-point register bank */
-
-def generate_bitfield(bits, start=0, end=31):
-    res = 0
-    current = start
-    for name, index, length in bits:
-        if index != current:
-            size = index - current
-            yield f"_res{res}", size
-            res += 1
-        yield name, length
-        current = index + 1
-
-    end_len = end + 1
-    if current != end_len:
-        yield f"_res{res}", end_len - current
-
-def generate_bitfield_little(bits):
-    return generate_bitfield(bits)
-
-def generate_bitfield_big(bits):
-    return reversed(list(generate_bitfield(bits)))
-
-def generate(struct_name, bits):
-    yield "#pragma once"
-    yield ""
-    yield "#include <stdint.h>"
-    yield ""
-    yield f"struct {struct_name} {{"
-    yield "#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__"
-    for name, size in generate_bitfield_little(bits):
-        yield f"  uint32_t {name.lower()} : {size};"
-    yield "#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__"
-    for name, size in generate_bitfield_big(bits):
-        yield f"  uint32_t {name.lower()} : {size};"
-    yield "#else"
-    yield '# error "unsupported endianness"'
-    yield "#endif"
-    yield "};"
-
-if __name__ == "__main__":
-    print('\n'.join(generate("sr_bits", sr_bits)))

build.sh

@@ -1,3 +1,3 @@
-PYTHONPATH=python/ python transform.py c/impl.c c/impl.h
+PYTHONPATH=python/ python generate_impl.py c/impl.c c/impl.h
 PYTHONPATH=python/ python generate_decoder.py c/decode_execute.c c/decode_print.c
-PYTHONPATH=python/ python bitfield.py > c/sr_bits.h
+PYTHONPATH=python/ python generate_bits.py > c/status_bits.h

c/impl.h

@@ -183,10 +183,14 @@ void rotr__destination_operand_only(struct architectural_state * state, struct m
 void rotcl__destination_operand_only(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* ROTCR Rn */
 void rotcr__destination_operand_only(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* SHAD Rm,Rn */
+void shad__source_and_destination_operands(struct architectural_state * state, struct memory_map * map, const uint32_t m, const uint32_t n);
 /* SHAL Rn */
 void shal__destination_operand_only(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* SHAR Rn */
 void shar__destination_operand_only(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* SHLD Rm,Rn */
+void shld__source_and_destination_operands(struct architectural_state * state, struct memory_map * map, const uint32_t m, const uint32_t n);
 /* SHLL Rn */
 void shll__destination_operand_only(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* SHLR Rn */
@@ -237,12 +241,28 @@ void ldc__transfer_to_sr(struct architectural_state * state, struct memory_map *
 void ldc__transfer_to_gbr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
 /* LDC Rm,VBR */
 void ldc__transfer_to_vbr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC Rm,SSR */
+void ldc__transfer_to_ssr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC Rm,SPC */
+void ldc__transfer_to_spc(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC Rm,DBR */
+void ldc__transfer_to_dbr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC Rm,Rn_BANK */
+void ldc__transfer_to_rn_bank(struct architectural_state * state, struct memory_map * map, const uint32_t m, const uint32_t n);
 /* LDC.L @Rm+,SR */
 void ldc_l__load_to_sr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
 /* LDC.L @Rm+,GBR */
 void ldc_l__load_to_gbr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
 /* LDC.L @Rm+,VBR */
 void ldc_l__load_to_vbr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC.L @Rm+,SSR */
+void ldc_l__load_to_ssr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC.L @Rm+,SPC */
+void ldc_l__load_to_spc(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC.L @Rm+,DBR */
+void ldc_l__load_to_dbr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDC.L @Rm+,Rn_BANK */
+void ldc_l__load_to_rn_bank(struct architectural_state * state, struct memory_map * map, const uint32_t m, const uint32_t n);
 /* LDS Rm,MACH */
 void lds__transfer_to_mach(struct architectural_state * state, struct memory_map * map, const uint32_t m);
 /* LDS Rm,MACL */
@@ -271,12 +291,32 @@ void stc__transfer_from_sr(struct architectural_state * state, struct memory_map
 void stc__transfer_from_gbr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* STC VBR,Rn */
 void stc__transfer_from_vbr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC SSR,Rn */
+void stc__transfer_from_ssr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC SPC,Rn */
+void stc__transfer_from_spc(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC SGR,Rn */
+void stc__transfer_from_sgr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC DBR,Rn */
+void stc__transfer_from_dbr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC Rm_BANK,Rn */
+void stc__transfer_from_rm_bank(struct architectural_state * state, struct memory_map * map, const uint32_t m, const uint32_t n);
 /* STC.L SR,@-Rn */
 void stc_l__store_from_sr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* STC.L GBR,@-Rn */
 void stc_l__store_from_gbr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* STC.L VBR,@-Rn */
 void stc_l__store_from_vbr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC.L SSR,@-Rn */
+void stc_l__store_from_ssr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC.L SPC,@-Rn */
+void stc_l__store_from_spc(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC.L SGR,@-Rn */
+void stc_l__store_from_sgr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC.L DBR,@-Rn */
+void stc_l__store_from_dbr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STC.L Rm_BANK,@-Rn */
+void stc_l__store_from_rm_bank(struct architectural_state * state, struct memory_map * map, const uint32_t m, const uint32_t n);
 /* STS MACH,Rn */
 void sts__transfer_from_mach(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* STS MACL,Rn */
@@ -290,4 +330,20 @@ void sts_l__store_from_macl(struct architectural_state * state, struct memory_ma
 /* STS.L PR,@-Rn */
 void sts_l__store_from_pr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
 /* TRAPA #imm */
-void trapa__immediate(struct architectural_state * state, struct memory_map * map, const uint32_t i);
+void trapa__immediate(struct architectural_state * state, struct memory_map * map, const uint32_t i);
+/* LDS Rm,FPSCR */
+void lds__transfer_to_fpscr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDS Rm,FPUL */
+void lds__transfer_to_fpul(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDS.L @Rm+,FPSCR */
+void lds_l__load_to_fpscr(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* LDS.L @Rm+,FPUL */
+void lds_l__load_to_fpul(struct architectural_state * state, struct memory_map * map, const uint32_t m);
+/* STS FPSCR,Rn */
+void sts__transfer_from_fpscr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STS FPUL,Rn */
+void sts__transfer_from_fpul(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STS.L FPSCR,@-Rn */
+void sts_l__store_from_fpscr(struct architectural_state * state, struct memory_map * map, const uint32_t n);
+/* STS.L FPUL,@-Rn */
+void sts_l__store_from_fpul(struct architectural_state * state, struct memory_map * map, const uint32_t n);

c/operations.h

@@ -64,6 +64,11 @@ static inline uint32_t zero_extend8(uint32_t x)
   return zero_extend(x, 8);
 }
 
+static inline uint32_t zero_extend5(uint32_t x)
+{
+  return zero_extend(x, 5);
+}
+
 static inline uint32_t zero_extend4(uint32_t x)
 {
   return zero_extend(x, 4);

c/sr_bits.h

@@ -1,39 +0,0 @@
-#pragma once
-
-#include <stdint.h>
-
-struct sr_bits {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-  uint32_t t : 1;
-  uint32_t s : 1;
-  uint32_t _res0 : 2;
-  uint32_t imask : 4;
-  uint32_t _res1 : 3;
-  uint32_t q : 1;
-  uint32_t m : 1;
-  uint32_t _res2 : 5;
-  uint32_t fd : 1;
-  uint32_t _res3 : 12;
-  uint32_t bl : 1;
-  uint32_t rb : 1;
-  uint32_t md : 1;
-  uint32_t _res4 : 1;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-  uint32_t _res4 : 1;
-  uint32_t md : 1;
-  uint32_t rb : 1;
-  uint32_t bl : 1;
-  uint32_t _res3 : 12;
-  uint32_t fd : 1;
-  uint32_t _res2 : 5;
-  uint32_t m : 1;
-  uint32_t q : 1;
-  uint32_t _res1 : 3;
-  uint32_t imask : 4;
-  uint32_t _res0 : 2;
-  uint32_t s : 1;
-  uint32_t t : 1;
-#else
-# error "unsupported endianness"
-#endif
-};

c/state.h

@@ -4,7 +4,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 
-#include "sr_bits.h"
+#include "status_bits.h"
 
 #define SR__RB (1 << 29)
 #define SR__MD (1 << 30)
@@ -33,6 +33,29 @@ static_assert(REGN_BANK(SR__MD | SR__RB, 7 ) == 7 );
 static_assert(REGN_BANK(SR__MD | SR__RB, 8 ) == 8 );
 static_assert(REGN_BANK(SR__MD | SR__RB, 15) == 15);
 
+union floating_point_registers {
+  uint32_t fr[32];
+  uint32_t fp[16][2];
+  uint64_t dr[16];
+  uint32_t fv[8][4];
+  uint32_t fm[2][16];
+};
+
+static_assert((sizeof (union floating_point_registers)) == 32 * 4);
+
+#define FR_N(state, x) ((x) ^ ((state)->fpscr.fr << 4))
+#define FR_(state, x) ((state)->floating_point_register.fr[FR_N(state, x)])
+#define FP_N(state, x) ((x) ^ ((state)->fpscr.fr << 3))
+#define FP_(state, x) ((state)->floating_point_register.fp[FP_N(state, x)])
+#define DR2_N(state, x) ((x) ^ ((state)->fpscr.fr << 3))
+#define DR2_(state, x) ((state)->floating_point_register.dr[DR2_N(state, x)])
+#define XD2_N(state, x) ((x) ^ ((!(state)->fpscr.fr) << 3))
+#define XD2_(state, x) ((state)->floating_point_register.dr[XD2_N(state, x)])
+#define FV4_N(state, x) ((x) ^ ((state)->fpscr.fr << 2))
+#define FV4_(state, x) ((state)->floating_point_register.dr[FV4_N(state, x)])
+#define XMTRX_N(state) (!(state)->fpscr.fr)
+#define XMTRX(state) ((state)->floating_point_register.fm[XMTRX_N(state)])
+
 struct architectural_state {
   uint32_t general_register[24];
 
@@ -41,7 +64,10 @@ struct architectural_state {
   uint32_t macl;
   uint32_t pr[3];
   uint32_t pc[3];
-  uint32_t fpscr;
+  union {
+    struct fpscr_bits bits;
+    uint32_t value;
+  } fpscr;
   uint32_t fpul;
   //
 
@@ -58,7 +84,7 @@ struct architectural_state {
   uint32_t dbr;
   //
 
-  uint32_t floating_point_register[32];
+  union floating_point_registers floating_point_register;
 
   bool is_delay_slot;
 };

c/state_helpers.h

@@ -5,12 +5,28 @@
 
 #include "state.h"
 #include "memory_map.h"
+#include "status_bits.h"
 
 static inline bool is_delay_slot(struct architectural_state * state)
 {
   return state->is_delay_slot;
 }
 
+static inline struct sr_bits _sr_bits(uint32_t sr)
+{
+  union {
+    struct sr_bits bits;
+    uint32_t value;
+  } sr_union;
+  sr_union.value = sr;
+  return sr_union.bits;
+}
+
+static inline bool fpu_is_disabled(uint32_t sr)
+{
+  return _sr_bits(sr).fd;
+}
+
 static inline void sleep(struct architectural_state * state)
 {
 }

c/status_bits.h

@@ -0,0 +1,96 @@
+#pragma once
+
+#include <stdint.h>
+
+
+struct sr_bits {
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+  uint32_t t : 1;
+  uint32_t s : 1;
+  uint32_t _res0 : 2;
+  uint32_t imask : 4;
+  uint32_t _res1 : 3;
+  uint32_t q : 1;
+  uint32_t m : 1;
+  uint32_t _res2 : 5;
+  uint32_t fd : 1;
+  uint32_t _res3 : 12;
+  uint32_t bl : 1;
+  uint32_t rb : 1;
+  uint32_t md : 1;
+  uint32_t _res4 : 1;
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+  uint32_t _res4 : 1;
+  uint32_t md : 1;
+  uint32_t rb : 1;
+  uint32_t bl : 1;
+  uint32_t _res3 : 12;
+  uint32_t fd : 1;
+  uint32_t _res2 : 5;
+  uint32_t m : 1;
+  uint32_t q : 1;
+  uint32_t _res1 : 3;
+  uint32_t imask : 4;
+  uint32_t _res0 : 2;
+  uint32_t s : 1;
+  uint32_t t : 1;
+#else
+# error "unsupported endianness"
+#endif
+};
+
+
+struct fpscr_bits {
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+  uint32_t rm : 1;
+  uint32_t _res0 : 1;
+  uint32_t flag_inexact : 1;
+  uint32_t flag_underflow : 1;
+  uint32_t flag_overflow : 1;
+  uint32_t flag_division_by_zero : 1;
+  uint32_t flag_invalid_operation : 1;
+  uint32_t enable_inexact : 1;
+  uint32_t enable_underflow : 1;
+  uint32_t enable_overflow : 1;
+  uint32_t enable_division_by_zero : 1;
+  uint32_t enable_invalid : 1;
+  uint32_t cause_inexact : 1;
+  uint32_t cause_underflow : 1;
+  uint32_t cause_overflow : 1;
+  uint32_t cause_division_by_zero : 1;
+  uint32_t cause_invalid : 1;
+  uint32_t cause_fpu_error : 1;
+  uint32_t dn : 1;
+  uint32_t pr : 1;
+  uint32_t sz : 1;
+  uint32_t fr : 1;
+  uint32_t _res1 : 10;
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+  uint32_t _res1 : 10;
+  uint32_t fr : 1;
+  uint32_t sz : 1;
+  uint32_t pr : 1;
+  uint32_t dn : 1;
+  uint32_t cause_fpu_error : 1;
+  uint32_t cause_invalid : 1;
+  uint32_t cause_division_by_zero : 1;
+  uint32_t cause_overflow : 1;
+  uint32_t cause_underflow : 1;
+  uint32_t cause_inexact : 1;
+  uint32_t enable_invalid : 1;
+  uint32_t enable_division_by_zero : 1;
+  uint32_t enable_overflow : 1;
+  uint32_t enable_underflow : 1;
+  uint32_t enable_inexact : 1;
+  uint32_t flag_invalid_operation : 1;
+  uint32_t flag_division_by_zero : 1;
+  uint32_t flag_overflow : 1;
+  uint32_t flag_underflow : 1;
+  uint32_t flag_inexact : 1;
+  uint32_t _res0 : 1;
+  uint32_t rm : 1;
+#else
+# error "unsupported endianness"
+#endif
+};
+

generate_bits.py

@@ -0,0 +1,79 @@
+sr_bits = (
+    ("T"    , 0 , 1),  # true/false condition
+    ("S"    , 1 , 1),  # saturation
+    ("IMASK", 4 , 4),  # interrupt mask level, 4 bits
+    ("Q"    , 8 , 1),  # state for divide step
+    ("M"    , 9 , 1),  # state for divide step
+    ("FD"   , 15, 1),  # FPU disable
+    ("BL"   , 28, 1),  # Exception/interrupt block bit
+    ("RB"   , 29, 1),  # General register bank specifier in privileged mode
+    ("MD"   , 30, 1),  # Processor mode
+)
+
+fpscr_bits = (
+    ("RM"                     , 0,  1), # Rounding mode
+    ("FLAG_INEXACT"           , 2,  1),
+    ("FLAG_UNDERFLOW"         , 3,  1),
+    ("FLAG_OVERFLOW"          , 4,  1),
+    ("FLAG_DIVISION_BY_ZERO"  , 5,  1),
+    ("FLAG_INVALID_OPERATION" , 6,  1),
+    ("ENABLE_INEXACT"         , 7,  1),
+    ("ENABLE_UNDERFLOW"       , 8,  1),
+    ("ENABLE_OVERFLOW"        , 9,  1),
+    ("ENABLE_DIVISION_BY_ZERO", 10, 1),
+    ("ENABLE_INVALID"         , 11, 1),
+    ("CAUSE_INEXACT"          , 12, 1),
+    ("CAUSE_UNDERFLOW"        , 13, 1),
+    ("CAUSE_OVERFLOW"         , 14, 1),
+    ("CAUSE_DIVISION_BY_ZERO" , 15, 1),
+    ("CAUSE_INVALID"          , 16, 1),
+    ("CAUSE_FPU_ERROR"        , 17, 1),
+    ("DN"                     , 18, 1), # Denormalization mode
+    ("PR"                     , 19, 1), # Precision mode
+    ("SZ"                     , 20, 1), # Transfer size mode
+    ("FR"                     , 21, 1), # Floating-point register bank
+)
+
+def generate_bitfield(bits, start=0, end=31):
+    res = 0
+    current = start
+    for name, index, length in bits:
+        if index != current:
+            size = index - current
+            yield f"_res{res}", size
+            res += 1
+        yield name, length
+        current = index + 1
+
+    end_len = end + 1
+    if current != end_len:
+        yield f"_res{res}", end_len - current
+
+def generate_bitfield_little(bits):
+    return generate_bitfield(bits)
+
+def generate_bitfield_big(bits):
+    return reversed(list(generate_bitfield(bits)))
+
+def generate(struct_name, bits):
+    yield ""
+    yield f"struct {struct_name} {{"
+    yield "#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__"
+    for name, size in generate_bitfield_little(bits):
+        yield f"  uint32_t {name.lower()} : {size};"
+    yield "#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__"
+    for name, size in generate_bitfield_big(bits):
+        yield f"  uint32_t {name.lower()} : {size};"
+    yield "#else"
+    yield '# error "unsupported endianness"'
+    yield "#endif"
+    yield "};"
+    yield ""
+
+if __name__ == "__main__":
+    print("#pragma once")
+    print()
+    print("#include <stdint.h>")
+    print()
+    print('\n'.join(generate("sr_bits", sr_bits)))
+    print('\n'.join(generate("fpscr_bits", fpscr_bits)))

generate_impl.py

@@ -3,7 +3,8 @@ import os
 
 from lexer import Lexer
 from parser import Parser
-from generator import generate, CTX
+from ast_to_c_source import generate
+from ast_transformers import transform_statements
 
 from instruction_table import untabulate_instructions_sh4
 from instruction_table import untabulate_instructions_sh2
@@ -52,17 +53,20 @@ def generate_function_declaration(instruction_name, function_name, variables):
     yield f"void {function_name}({args})"
 
 def generate_file(instruction_name, function_name, variables, delay_slot, src_path):
+    print(instruction_name)
     tokens = list(parse_file(src_path))
     parser = Parser(tokens)
+    statements = []
+    while parser.tokens[parser.pos:]:
+        statements.append(parser.statement())
 
-    ctx = CTX(identifiers=set())
+    statements = transform_statements(statements)
 
     yield from generate_function_declaration(instruction_name, function_name, variables)
     yield "{"
     output = []
-    while parser.tokens[parser.pos:]:
-        stmt = parser.statement()
-        src = "".join(generate(ctx, stmt))
+    for statement in statements:
+        src = "".join(generate(statement))
         output.append(src)
 
     for line in "".join(output).rstrip().split('\n'):
@@ -90,10 +94,49 @@ def main():
         '',
     ]
 
-    sh2_instructions = set((ins.instruction, ins.operands) for ins in untabulate_instructions_sh2())
+    skip = [
+        "FLDS",
+        "FSTS",
+        "FABS",
+        "FADD",
+        "FCMP/EQ",
+        "FCMP/GT",
+        "FDIV",
+        "FLOAT",
+        "FMAC",
+        "FMUL",
+        "FNEG",
+        "FSQRT",
+        "FSUB",
+        "FTRC",
+        "FCNVDS",
+        "FCNVSD",
+        "FRCHG",
+        "FSCHG",
+        "FCSA",
+        "FSRRA",
+        "FIPR",
+        "FTRV",
+
+        "FLDI0",
+        "FLDI1",
+        "FMOV",
+        "FMOV.S",
+
+        "LDTLB",
+        "OCBI",
+        "OCBP",
+        "OCBWB",
+        "PREF",
+
+        "MOVCA.L",
+        "BRK",
+    ]
+
     for ins in untabulate_instructions_sh4():
-        if (ins.instruction, ins.operands) not in sh2_instructions:
+        if ins.instruction in skip:
             continue
+
         _name = [ins.instruction, ins.operands] if ins.operands else [ins.instruction]
         instruction_name = " ".join(_name)
         function_name = instruction_function_name(ins)

generator.py

@@ -1,301 +0,0 @@
-from dataclasses import dataclass
-
-from parser import Tree
-from lexer import Identifier, Punctuator, IntegerConstant
-import identifier_substitution
-
-@dataclass
-class CTX:
-    identifiers: set
-
-def argument_list(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield ", "
-    yield from generate(ctx, tree.children[1])
-
-def _is_new_temporary(ctx, tree):
-    return (
-        type(tree) is Identifier
-        and tree.token not in identifier_substitution.mapping
-        and tree.token not in ctx.identifiers
-    )
-
-def assignment(ctx, tree):
-    lhs = tree.children[0]
-    rhs = tree.children[1]
-    if _is_new_temporary(ctx, lhs):
-        ctx.identifiers.add(lhs.token)
-        yield "int64_t "
-
-    yield from generate(ctx, tree.children[0])
-    yield " = "
-    yield from generate(ctx, tree.children[1])
-
-def bit_extraction(ctx, tree):
-    yield "bit_extract("
-    yield from generate(ctx, tree.children[0])
-    yield ", "
-    yield from generate(ctx, tree.children[1])
-    yield ")"
-
-def bitwise_and(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " & "
-    yield from generate(ctx, tree.children[1])
-
-def bitwise_or(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " | "
-    yield from generate(ctx, tree.children[1])
-
-def bitwise_xor(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " ^ "
-    yield from generate(ctx, tree.children[1])
-
-def block_item_list(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield from generate(ctx, tree.children[1])
-
-def compound_statement(ctx, tree):
-    yield "\n{\n"
-    if tree.children:
-        yield from generate(ctx, tree.children[0])
-    yield "}\n"
-
-def expression_statement(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield ";\n"
-
-def for_expression(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield ", "
-    if len(tree.children) > 1:
-        yield from generate(ctx, tree.children[1])
-    else:
-        yield "1"
-
-def helper_arguments(tree):
-    if type(tree.children[0]) is not Identifier:
-        return
-    name = tree.children[0].token
-    mapping = {
-        "IsDelaySlot": "state",
-        "SLEEP": "state",
-        "OCBP" : "state",
-        "WriteMemory8" : "map",
-        "WriteMemory16": "map",
-        "WriteMemory32": "map",
-        "ReadMemory8"  : "map",
-        "ReadMemory16" : "map",
-        "ReadMemory32" : "map",
-    }
-    return mapping.get(name, None)
-
-def function_call(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield "("
-    if len(tree.children) >= 2:
-        if helper_arguments(tree):
-            yield helper_arguments(tree)
-            yield ", "
-        yield from generate(ctx, tree.children[1])
-    else:
-        if helper_arguments(tree):
-            yield helper_arguments(tree)
-    yield ")"
-
-def grouping(ctx, tree):
-    yield "("
-    yield from generate(ctx, tree.children[0])
-    yield ")"
-
-def _if(ctx, tree):
-    yield "if ("
-    yield from generate(ctx, tree.children[0])
-    yield ") "
-    yield from generate(ctx, tree.children[1])
-
-def if_else(ctx, tree):
-    yield "if ("
-    yield from generate(ctx, tree.children[0])
-    yield ") "
-    yield from generate(ctx, tree.children[1])
-    yield "else "
-    yield from generate(ctx, tree.children[2])
-
-def logical_and(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " && "
-    yield from generate(ctx, tree.children[1])
-
-def logical_or(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " || "
-    yield from generate(ctx, tree.children[1])
-
-def member(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield "."
-    yield from generate(ctx, tree.children[1])
-
-def subscript(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield "["
-    yield from generate(ctx, tree.children[1])
-    yield "]"
-
-def throw(ctx, tree):
-    yield "return "
-    yield from generate(ctx, tree.children[0])
-    yield "(state);\n"
-
-def throw_arg(ctx, tree):
-    yield "return "
-    yield from generate(ctx, tree.children[0])
-    yield "(state, "
-    yield from generate(ctx, tree.children[1])
-    yield ");\n"
-
-def unary_complement(ctx, tree):
-    yield from "~"
-    yield from generate(ctx, tree.children[0])
-
-def unary_int(ctx, tree):
-    yield "unary_int("
-    yield from generate(ctx, tree.children[0])
-    yield ")"
-
-def unary_negation(ctx, tree):
-    yield "-"
-    yield from generate(ctx, tree.children[0])
-
-def unary_not(ctx, tree):
-    yield "!"
-    yield from generate(ctx, tree.children[0])
-
-#
-def addition(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " + "
-    yield from generate(ctx, tree.children[1])
-
-def division(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " / "
-    yield from generate(ctx, tree.children[1])
-
-def equality_equal(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " == "
-    yield from generate(ctx, tree.children[1])
-
-def equality_not_equal(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " != "
-    yield from generate(ctx, tree.children[1])
-
-def greater_than(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " > "
-    yield from generate(ctx, tree.children[1])
-
-def greater_than_equal(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " >= "
-    yield from generate(ctx, tree.children[1])
-
-def left_shift(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    # hack for left shift by LHS constant
-    if type(tree.children[0]) is IntegerConstant:
-        yield "LL"
-    yield " << "
-    yield from generate(ctx, tree.children[1])
-
-def less_than(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " < "
-    yield from generate(ctx, tree.children[1])
-
-def less_than_equal(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " <= "
-    yield from generate(ctx, tree.children[1])
-
-def multiplication(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " * "
-    yield from generate(ctx, tree.children[1])
-
-def right_shift(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " >> "
-    yield from generate(ctx, tree.children[1])
-
-def subtraction(ctx, tree):
-    yield from generate(ctx, tree.children[0])
-    yield " - "
-    yield from generate(ctx, tree.children[1])
-
-def identifier(ctx, token):
-    if token.token in identifier_substitution.mapping:
-        yield identifier_substitution.mapping[token.token]
-    else:
-        assert token.token.lower() == token.token, token
-        if token.token not in {'m', 'n', 'i', 'd'}:
-            assert token.token in ctx.identifiers, (token, ctx.identifiers)
-        yield token.token
-
-def constant(ctx, elem):
-    yield elem.token.lower()
-
-def generate(ctx, elem):
-    mapping = {
-        "argument_list": argument_list,
-        "assignment": assignment,
-        "bit_extraction": bit_extraction,
-        "bitwise_and": bitwise_and,
-        "bitwise_or": bitwise_or,
-        "bitwise_xor": bitwise_xor,
-        "block_item_list": block_item_list,
-        "compound_statement": compound_statement,
-        "expression_statement": expression_statement,
-        "for_expression": for_expression,
-        "function_call": function_call,
-        "grouping": grouping,
-        "if": _if,
-        "if_else": if_else,
-        "logical_and": logical_and,
-        "logical_or": logical_or,
-        "member": member,
-        "subscript": subscript,
-        "throw": throw,
-        "throw_arg": throw_arg,
-        "unary_complement": unary_complement,
-        "unary_int": unary_int,
-        "unary_negation": unary_negation,
-        "unary_not": unary_not,
-        #
-        "addition": addition,
-        "division": division,
-        "equality_equal": equality_equal,
-        "equality_not_equal": equality_not_equal,
-        "greater_than": greater_than,
-        "greater_than_equal": greater_than_equal,
-        "left_shift": left_shift,
-        "less_than": less_than,
-        "less_than_equal": less_than_equal,
-        "multiplication": multiplication,
-        "right_shift": right_shift,
-        "subtraction": subtraction,
-        #
-    }
-    if type(elem) is Tree:
-        yield from mapping[elem.operation](ctx, elem)
-    elif type(elem) is Identifier:
-        yield from identifier(ctx, elem)
-    elif type(elem) is IntegerConstant:
-        yield from constant(ctx, elem)
-    else:
-        assert False, type(elem)

identifier_substitution.py

@@ -28,7 +28,7 @@ mapping = {
     "PC"              : "state->pc[0]",
     "PC’"             : "state->pc[1]",
     "PC’’"            : "state->pc[2]",
-    "FPSCR"           : "state->fpscr",
+    "FPSCR"           : "state->fpscr.value",
     "FPUL"            : "state->fpul",
 
     "SR"              : "state->sr.value",
@@ -71,37 +71,111 @@ mapping = {
     "IsDelaySlot"     : "is_delay_slot",
     "SLEEP"           : "sleep",
     "OCBP"            : "ocbp",
+
+    "ASID"            : "ASID",
+    "VPN"             : "VPN",
+    "PPN"             : "PPN",
+    "SZ"              : "SZ",
+    "SZ0"             : "SZ0",
+    "SZ1"             : "SZ1",
+    "SH"              : "SH",
+    "WT"              : "WT",
+    "C"               : "C",
+    "D"               : "D",
+    "V"               : "V",
+
+    "ALLOCO"          : "ALLOCO",
+    "MMU"             : "MMU",
+    "MMUCR"           : "MMUCR",
+    "OCBI"            : "OCBI",
+    "OCBWB"           : "OCBWB",
+    "PREF"            : "PREF",
+    "PTEH"            : "PTEH",
+    "PTEL"            : "PTEL",
+    "URC"             : "URC",
+    "UTLB"            : "UTLB",
+
+    "AddressUnavailable": "address_unavailable",
+    "DataAccessMiss"  : "data_access_miss",
+    "DirtyBit"        : "dirty_bit",
+    "ReadProhibited"  : "read_prohibited",
+    "WriteProhibited" : "write_prohibited",
+
+    "FR0"             : "FR_(state, 0)",
+    "FRm"             : "FR_(state, m)",
+    "FRn"             : "FR_(state, n)",
+    "FP2m"            : "FP2_(state, m)",
+    "FP2n"            : "FP2_(state, n)",
+    "DR2m"            : "DR2_(state, m)",
+    "DR2n"            : "DR2_(state, n)",
+    "XD2m"            : "XD2_(state, m)",
+    "XD2n"            : "XD2_(state, n)",
+    "FV4n"            : "FV4_(state, n)",
+    "FV4m"            : "FV4_(state, m)",
+    "XMTRX"           : "XMTRX(state)",
+
+    "FR"              : "fr",
+
+    "ReadMemoryPair32"    : "read_memory_pair32",
+    "WriteMemoryPair32"   : "write_memory_pair32",
+
+    "FloatRegister32"      : "float_register32",
+    "FloatRegister64"      : "float_register64",
+    "FloatRegisterPair32"  : "float_register_pair32",
+    "FloatRegisterVector32": "float_register_vector32",
+    "FloatValue32"         : "float_value32",
+    "FloatValue64"         : "float_value64",
+    "FloatValuePair32"     : "float_value_pair32",
+    "FloatValueVector32"   : "float_value_vector32",
+    "FloatValueMatrix32"   : "float_value_matrix32",
+
+    "FADD_S"              : "fadd_s",
+    "FADD_D"              : "fadd_d",
+    "FSUB_S"              : "fsub_s",
+    "FSUB_D"              : "fsub_d",
+    "FMUL_S"              : "fmul_s",
+    "FMUL_D"              : "fmul_d",
+    "FDIV_S"              : "fdiv_s",
+    "FDIV_D"              : "fdiv_d",
+
+    "FABS_S"              : "fabs_s",
+    "FABS_D"              : "fabs_d",
+    "FNEG_S"              : "fneg_s",
+    "FNEG_D"              : "fneg_d",
+    "FSQRT_S"             : "fsqrt_s",
+    "FSQRT_D"             : "fsqrt_d",
+
+    "FCMPEQ_S"            : "fcmpeq_s",
+    "FCMPEQ_D"            : "fcmpeq_d",
+    "FCMPGT_S"            : "fcmpgt_s",
+    "FCMPGT_D"            : "fcmpgt_d",
+
+    "FCNV_SD"             : "fcnv_sd",
+    "FCNV_DS"             : "fcnv_ds",
+    "FTRC_SL"             : "ftrc_sl",
+    "FTRC_DL"             : "ftrc_dl",
+    "FLOAT_LS"            : "float_ls",
+    "FLOAT_LD"            : "float_ld",
+
+    "FMAC_S"              : "fmac_s",
+    "FIPR_S"              : "fipr_s",
+    "FTRV_S"              : "ftrv_s",
+
+    "FpuIsDisabled"       : "fpu_is_disabled",
+    "FpuFlagI"            : "fpu_flag_I",
+    "FpuFlagU"            : "fpu_flag_U",
+    "FpuFlagO"            : "fpu_flag_O",
+    "FpuFlagZ"            : "fpu_flag_Z",
+    "FpuFlagV"            : "fpu_flag_V",
+    "FpuCauseI"           : "fpu_cause_I",
+    "FpuCauseU"           : "fpu_cause_U",
+    "FpuCauseO"           : "fpu_cause_O",
+    "FpuCauseZ"           : "fpu_cause_Z",
+    "FpuCauseV"           : "fpu_cause_V",
+    "FpuCauseE"           : "fpu_cause_E",
+    "FpuEnableI"          : "fpu_enable_I",
+    "FpuEnableU"          : "fpu_enable_U",
+    "FpuEnableO"          : "fpu_enable_O",
+    "FpuEnableZ"          : "fpu_enable_Z",
+    "FpuEnableV"          : "fpu_enable_V",
 }
-
-"""
-ASID
-VPN
-PPN
-SZ
-SZ0
-SZ1
-SH
-PR
-WT
-C
-D
-V
-
-AddressUnavailable
-ALLOCO
-DataAccessMiss
-DirtyBit
-FpuIsDisabled
-IsDelaySlot
-MMU
-MMUCR
-OCBI
-OCBWB
-PREF
-PTEH
-PTEL
-ReadProhibited
-URC
-UTLB
-WriteProhibited
-"""

parser.py

@@ -337,10 +337,23 @@ class Parser:
             )
         return expr
 
+    def assignment_list(self):
+        expr = self.unary_expression()
+        while True:
+            if self.match_punctuator(","):
+                right = self.unary_expression()
+                expr = Tree(
+                    operation="assignment_list",
+                    children=[expr, right]
+                )
+            else:
+                break
+        return expr
+
     def assignment_expression(self):
         backtrack = self.pos
         try:
-            left = self.unary_expression()
+            left = self.assignment_list()
         except AssertionError:
             self.pos = backtrack
             return self.logical_or_expression()

syntax.txt

@@ -88,9 +88,13 @@ logical-OR-expression:
 	logical-XOR-expression
 	logical-OR-expression "OR" logical-XOR-expression
 
+assignment-list:
+	unary-expression
+	assignment-lhs "," unary-expression
+
 assignment-expression:
 	logical-OR-expression
-	unary-expression "←" assignment-expression
+	assignment-list "←" assignment-expression
 
 expression:
 	assignment-expression

test_parser.py

@@ -1,6 +1,8 @@
+from pprint import pprint
+
 from lexer import Lexer
 from parser import Parser
-from generator import generate
+from ast_to_c_source import generate
 
 sources = [
     "op1 ← FloatValue64(DR2n);",
@@ -28,12 +30,13 @@ def all_tokens(lexer):
             break
         yield token
 
-for source in sources:
+def dump(source):
     lexer = Lexer(source)
     tokens = list(all_tokens(lexer))
     parser = Parser(tokens)
-    from pprint import pprint
     root = parser.statement()
-    s = "".join(generate(root))
-    print(s, end='')
-    print()
+    pprint(root)
+
+source = "c ← foobar(b, c, d);"
+
+dump(source);