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debug_class_file: print bootstrap methods

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This commit is contained in:
Zack Buhman 2025-01-06 08:28:23 -06:00
parent 832c182471
commit 6f8477e5f0
4 changed files with 154 additions and 11 deletions
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2
Makefile
View File

@ -7,7 +7,7 @@ CC ?= gcc
ARCH = -m32
CFLAGS += -Wall -Werror -Wfatal-errors -Wno-error=unused-variable -fstack-protector -std=c2x -g
CFLAGS += -DDEBUG
#CFLAGS += -DDEBUG_PRINT
CFLAGS += -DDEBUG_PRINT
LDFLAGS = -lm
OPT ?= -O0
DEPFLAGS = -MMD -MP

12
c/class_file.h
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@ -7,6 +7,18 @@ typedef uint32_t u4;
typedef uint16_t u2;
typedef uint8_t u1;
enum REF {
REF_getField = 1, // getfield C.f:T
REF_getStatic = 2, // getstatic C.f:T
REF_putField = 3, // putfield C.f:T
REF_putStatic = 4, // putstatic C.f:T
REF_invokeVirtual = 5, // invokevirtual C.m:(A*)T
REF_invokeStatic = 6, // invokestatic C.m:(A*)T
REF_invokeSpecial = 7, // invokespecial C.m:(A*)T
REF_newInvokeSpecial = 8, // new C; dup; invokespecial C.<init>:(A*)V
REF_invokeInterface = 9, // invokeinterface C.m:(A*)T
};
enum CONSTANT {
CONSTANT_Class = 7, // §4.4.1
CONSTANT_Fieldref = 9, // §4.4.2

137
c/debug_class_file.c
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@ -94,6 +94,117 @@ static void print_constant(struct constant * constant)
}
}
void print_methodref(const char * indent, struct constant * constant, struct constant * constant_pool)
{
assert(constant->tag == CONSTANT_Methodref || constant->tag == CONSTANT_InterfaceMethodref || constant->tag == CONSTANT_Fieldref);
struct constant * class_constant = &constant_pool[constant->methodref.class_index - 1];
assert(class_constant->tag == CONSTANT_Class);
struct constant * class_name_constant = &constant_pool[class_constant->class.name_index - 1];
assert(class_name_constant->tag == CONSTANT_Utf8);
struct constant * name_and_type_constant = &constant_pool[constant->methodref.name_and_type_index - 1];
assert(name_and_type_constant->tag == CONSTANT_NameAndType);
struct constant * method_name_constant = &constant_pool[name_and_type_constant->nameandtype.name_index - 1];
assert(method_name_constant->tag == CONSTANT_Utf8);
struct constant * method_descriptor_constant = &constant_pool[name_and_type_constant->nameandtype.descriptor_index - 1];
assert(method_descriptor_constant->tag == CONSTANT_Utf8);
prints(indent);
print_constant(class_constant);
prints(indent);
prints(" ");
print_constant(class_name_constant);
prints(indent);
print_constant(name_and_type_constant);
prints(indent);
prints(" ");
print_constant(method_name_constant);
prints(indent);
prints(" ");
print_constant(method_descriptor_constant);
}
static void print_methodhandle_constant(const char * indent, struct constant * methodhandle_constant, struct constant * constant_pool)
{
prints(indent);
assert(methodhandle_constant->tag == CONSTANT_MethodHandle);
print_constant(methodhandle_constant);
prints(indent);
prints(" reference_kind: ");
switch (methodhandle_constant->methodhandle.reference_kind) {
case REF_getField: prints("REF_getField\n"); break;
case REF_getStatic: prints("REF_getStatic\n"); break;
case REF_putField: prints("REF_putField\n"); break;
case REF_putStatic: prints("REF_putStatic\n"); break;
case REF_invokeVirtual: prints("REF_invokeVirtual\n"); break;
case REF_invokeStatic: prints("REF_invokeStatic\n"); break;
case REF_invokeSpecial: prints("REF_invokeSpecial\n"); break;
case REF_newInvokeSpecial: prints("REF_newInvokeSpecial\n"); break;
case REF_invokeInterface: prints("REF_invokeInterface\n"); break;
default:
assert(false);
break;
}
struct constant * constant = &constant_pool[methodhandle_constant->methodhandle.reference_index - 1];
prints(indent);
prints(" reference_index: ");
print_constant(constant);
char indent2[string_length(indent) + 4 + 1];
indent2[(sizeof (indent2)) - 1] = 0;
for (int i = 0; i < (sizeof (indent2)) - 1; i++) indent2[i] = ' ';
switch (methodhandle_constant->methodhandle.reference_kind) {
case REF_getField: [[fallthrough]];
case REF_getStatic: [[fallthrough]];
case REF_putField: [[fallthrough]];
case REF_putStatic:
// If the value of the reference_kind item is 1 (REF_getField), 2
// (REF_getStatic), 3 (REF_putField), or 4 (REF_putStatic), then the
// constant_pool entry at that index must be a CONSTANT_Fieldref_info
// structure (§4.4.2) representing a field for which a method handle is to be
// created.
assert(constant->tag == CONSTANT_Fieldref);
print_methodref(indent2, constant, constant_pool);
break;
case REF_invokeVirtual: [[fallthrough]];
case REF_newInvokeSpecial:
// If the value of the reference_kind item is 5 (REF_invokeVirtual) or 8
// (REF_newInvokeSpecial), then the constant_pool entry at that index must be
// a CONSTANT_Methodref_info structure (§4.4.2) representing a class's method
// or constructor (§2.9.1) for which a method handle is to be created.
assert(constant->tag == CONSTANT_Methodref);
print_methodref(indent2, constant, constant_pool);
break;
case REF_invokeStatic: [[fallthrough]];
case REF_invokeSpecial:
// If the value of the reference_kind item is 6 (REF_invokeStatic) or 7
// (REF_invokeSpecial), [...] the constant_pool entry at that index must be
// either a CONSTANT_Methodref_info structure or a
// CONSTANT_InterfaceMethodref_info structure (§4.4.2) representing a class's
// or interface's method for which a method handle is to be created.
assert(constant->tag == CONSTANT_Methodref || constant->tag == CONSTANT_InterfaceMethodref);
print_methodref(indent2, constant, constant_pool);
break;
case REF_invokeInterface:
// If the value of the reference_kind item is 9 (REF_invokeInterface), then
// the constant_pool entry at that index must be a
// CONSTANT_InterfaceMethodref_info structure representing an interface's
// method for which a method handle is to be created.
assert(constant->tag == CONSTANT_InterfaceMethodref);
print_methodref(indent2, constant, constant_pool);
break;
default:
assert(false);
break;
}
//reference_kind=6
//reference_index=36
}
static void print_bootstrap_methods(const char * indent, struct attribute_info * attribute, struct constant * constant_pool)
{
prints(indent);
@ -101,17 +212,24 @@ static void print_bootstrap_methods(const char * indent, struct attribute_info *
prints(indent);
printf("bootstrap methods:\n");
for (int i = 0; i < attribute->bootstrap_methods->num_bootstrap_methods; i++) {
struct bootstrap_method * bootstrap_method = &attribute->bootstrap_methods->bootstrap_methods[i];
prints(indent);
printf(" bootstrap_method %d:\n", i);
prints(indent);
printf(" bootstrap_method_ref: %d\n", attribute->bootstrap_methods->bootstrap_methods[i].bootstrap_method_ref);
prints(indent);
printf(" num_bootstrap_arguments: %d\n", attribute->bootstrap_methods->bootstrap_methods[i].num_bootstrap_arguments);
prints(indent);
printf(" bootstrap_method_ref: %d\n", bootstrap_method->bootstrap_method_ref);
struct constant * methodhandle_constant = &constant_pool[bootstrap_method->bootstrap_method_ref - 1];
assert(methodhandle_constant->tag == CONSTANT_MethodHandle);
char indent2[string_length(indent) + 6 + 1];
indent2[(sizeof (indent2)) - 1] = 0;
for (int i = 0; i < (sizeof (indent2)) - 1; i++) indent2[i] = ' ';
print_methodhandle_constant(indent2, methodhandle_constant, constant_pool);
prints(indent2);
printf("num_bootstrap_arguments: %d\n", bootstrap_method->num_bootstrap_arguments);
prints(indent2);
printf("bootstrap_arguments:\n");
for (int j = 0; j < attribute->bootstrap_methods->bootstrap_methods[i].num_bootstrap_arguments; j++) {
prints(indent);
printf(" bootstrap_argument %d: %d\n", j, attribute->bootstrap_methods->bootstrap_methods[i].bootstrap_arguments[j]);
for (int j = 0; j < bootstrap_method->num_bootstrap_arguments; j++) {
prints(indent2);
printf(" bootstrap_argument %d: %d\n", j, bootstrap_method->bootstrap_arguments[j]);
}
}
}
@ -201,8 +319,9 @@ static void print_code(const char * indent, struct attribute_info * attribute, s
printf("attributes:\n");
for (int i = 0; i < attribute->code->attributes_count; i++) {
char indent2[string_length(indent) + 2 + 1];
string_copy(indent2, indent);
string_copy(indent2 + string_length(indent), " ");
indent2[(sizeof (indent2)) - 1] = 0;
for (int i = 0; i < (sizeof (indent2)) - 1; i++)
indent2[i] = ' ';
prints(indent);
printf(" attribute %d:\n", i);
print_attribute(indent2, &attribute->code->attributes[i], constant_pool);

12
p/TestInvokeDynamic.java Normal file
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@ -0,0 +1,12 @@
package p;
class TestInvokeDynamic {
static int test(String a, String b) {
String c = a + b;
return c.length();
}
public static void main() {
test("asdf", "qwert");
}
}