1 files changed, 61 insertions, 0 deletions
diff --git a/tests/jmp_table.c b/tests/jmp_table.c
new file mode 100644
index 0000000..2ea14cd
--- /dev/null
+++ b/tests/jmp_table.c
@@ -0,0 +1,61 @@
+#include "test.h"
+
+#define NTARGETS ((size_t) 4)
+
+static void
+run_test(jit_state_t *j, uint8_t *arena_base, size_t arena_size)
+{
+	jit_begin(j, arena_base, arena_size);
+	size_t align = jit_enter_jit_abi(j, 0, 0, 0);
+	jit_load_args_1(j, jit_operand_gpr (JIT_OPERAND_ABI_POINTER, JIT_R0));
+
+	jit_reloc_t default_target = jit_bgei_u(j, JIT_R0, NTARGETS);
+
+	// FIXME: need ldxr with word stride, then can eliminate lshi.
+	jit_lshi(j, JIT_R0, JIT_R0, sizeof(intptr_t) == 4 ? 2 : 3);
+	jit_reloc_t table = jit_mov_addr(j, JIT_R1);
+	jit_ldxr(j, JIT_R1, JIT_R1, JIT_R0);
+	jit_jmpr(j, JIT_R1);
+
+	jit_begin_data (j, (NTARGETS + 1) * sizeof(intptr_t));
+	jit_align(j, sizeof(intptr_t));
+	jit_patch_here(j, table);
+	jit_reloc_t targets[NTARGETS];
+	jit_reloc_t tails[NTARGETS];
+	for (size_t i = 0; i < NTARGETS; i++) {
+		targets[i] = jit_emit_addr(j);
+	}
+	jit_end_data (j);
+
+	for (size_t i = 0; i < NTARGETS; i++) {
+		jit_patch_here(j, targets[i]);
+		jit_movi(j, JIT_R0, i * i);
+		tails[i] = jit_jmp(j);
+	}
+
+	jit_patch_here(j, default_target);
+	jit_movi(j, JIT_R0, 42);
+	for (int i = 0; i < NTARGETS; i++) {
+		jit_patch_here(j, tails[i]);
+	}
+	jit_leave_jit_abi(j, 0, 0, align);
+	jit_retr(j, JIT_R0);
+
+	jit_word_t (*f)(jit_word_t) = jit_end(j, NULL);
+
+	for (int i = -2; i < ((int) NTARGETS) + 2; i++) {
+		if (i < 0) {
+			ASSERT(f(i) == 42);
+		} else if (i < NTARGETS) {
+			ASSERT(f(i) == i * i);
+		} else {
+			ASSERT(f(i) == 42);
+		}
+	}
+}
+
+int
+main (int argc, char *argv[])
+{
+	return main_helper(argc, argv, run_test);
+}