Add push/pop test

tests/pushpop.c

@@ -0,0 +1,44 @@
+#include "test.h"
+
+static void
+run_test(jit_state_t *j, uint8_t *arena_base, size_t arena_size)
+{
+  const jit_gpr_t gpr[] = { JIT_R0, JIT_R1, JIT_R2, JIT_V0, JIT_V1, JIT_V2 };
+  const jit_fpr_t fpr[] = { JIT_F0, JIT_F1, JIT_F2 };
+
+  jit_begin(j, arena_base, arena_size);
+
+  const jit_arg_abi_t abi[] = { JIT_ARG_ABI_INTMAX };
+  jit_arg_t args[1];
+  const jit_anyreg_t regs[] = { { .gpr=JIT_R0 } };
+
+  jit_receive(j, 1, abi, args);
+  jit_load_args(j, 1, abi, args, regs);
+
+  for (int i=0; i<6; i++)
+    jit_pushr(j, gpr[i]);
+  for (int i=0; i<3; i++)
+    jit_pushr_d(j, fpr[i]);
+
+  // Stomple registers.
+  for (int i=0; i<6; i++)
+    jit_movi(j, gpr[i], 0xcabba9e5);
+  for (int i=0; i<3; i++)
+    jit_extr_d(j, fpr[i], gpr[i]);
+
+  for (int i=2; i>=0; i--)
+    jit_popr_d(j, fpr[i]);
+  for (int i=5; i>=0; i--)
+    jit_popr(j, gpr[i]);
+
+  jit_retr(j, JIT_R0);
+
+  intmax_t (*f)(intmax_t) = jit_end(j, NULL);
+  ASSERT(f(42) == 42);
+}
+
+int
+main (int argc, char *argv[])
+{
+  return main_helper(argc, argv, run_test);
+}