feat: allow any division divisor

1 files changed, 22 insertions, 0 deletions

diff --git a/tests/codegen_test.c b/tests/codegen_test.c
index c92dfc2..2ccba98 100644
--- a/tests/codegen_test.c
+++ b/tests/codegen_test.c
@@ -241,6 +241,27 @@ static void test_generate_divide_nonrax(struct TestContext* context)
 	free_program(&program);
 }
 
+static void test_generate_divide_scratch(struct TestContext* context)
+{
+	// an immediate or rax/rdx divisor is routed through the r11 scratch
+	struct Lexer lexer = create_lexer(
+		"proc main\n{\nrbx /= 10\nrcx /= rax\nrsi = rdi / rdx\nr11 /= rax\n}\n");
+	struct Program program;
+	check(context, parse_program(&lexer, &program));
+
+	char buffer[1024];
+	generate_to_buffer(&program, buffer, sizeof(buffer));
+
+	check(context, strstr(buffer, "mov r11, 10") != NULL);   // immediate
+	check(context, strstr(buffer, "mov r11, rax") != NULL);  // rax divisor saved
+	check(context, strstr(buffer, "mov r11, rdx") != NULL);  // rdx divisor saved
+	check(context, strstr(buffer, "xchg rax, r11") != NULL); // dst is the scratch
+	check(context, strstr(buffer, "idiv r11") != NULL);
+	check(context, strstr(buffer, "; TODO") == NULL);
+
+	free_program(&program);
+}
+
 static void test_generate_stack_frame(struct TestContext* context)
 {
 	struct Lexer lexer = create_lexer("proc work\n{\nstack buffer[32]\nsyscall\n}\n");
@@ -514,6 +535,7 @@ void run_codegen_tests(struct TestContext* context)
 	test_generate_multiply(context);
 	test_generate_modulo(context);
 	test_generate_divide_nonrax(context);
+	test_generate_divide_scratch(context);
 	test_generate_stack_frame(context);
 	test_generate_address_expr(context);
 	test_generate_sized_store(context);