target/s390x: Make translator stop before the end of a page

Right now translator stops right *after* the end of a page, which
breaks reporting of fault locations when the last instruction of a
multi-insn translation block crosses a page boundary.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220817150506.592862-3-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 106 insertions, 0 deletions

diff --git a/tests/tcg/s390x/noexec.c b/tests/tcg/s390x/noexec.c
new file mode 100644
index 0000000..15d007d
--- /dev/null
+++ b/tests/tcg/s390x/noexec.c
@@ -0,0 +1,106 @@
+#include "../multiarch/noexec.c.inc"
+
+static void *arch_mcontext_pc(const mcontext_t *ctx)
+{
+    return (void *)ctx->psw.addr;
+}
+
+static int arch_mcontext_arg(const mcontext_t *ctx)
+{
+    return ctx->gregs[2];
+}
+
+static void arch_flush(void *p, int len)
+{
+}
+
+extern char noexec_1[];
+extern char noexec_2[];
+extern char noexec_end[];
+
+asm("noexec_1:\n"
+    "   lgfi %r2,1\n"       /* %r2 is 0 on entry, set 1. */
+    "noexec_2:\n"
+    "   lgfi %r2,2\n"       /* %r2 is 0/1; set 2. */
+    "   br %r14\n"          /* return */
+    "noexec_end:");
+
+extern char exrl_1[];
+extern char exrl_2[];
+extern char exrl_end[];
+
+asm("exrl_1:\n"
+    "   exrl %r0, exrl_2\n"
+    "   br %r14\n"
+    "exrl_2:\n"
+    "   lgfi %r2,2\n"
+    "exrl_end:");
+
+int main(void)
+{
+    struct noexec_test noexec_tests[] = {
+        {
+            .name = "fallthrough",
+            .test_code = noexec_1,
+            .test_len = noexec_end - noexec_1,
+            .page_ofs = noexec_1 - noexec_2,
+            .entry_ofs = noexec_1 - noexec_2,
+            .expected_si_ofs = 0,
+            .expected_pc_ofs = 0,
+            .expected_arg = 1,
+        },
+        {
+            .name = "jump",
+            .test_code = noexec_1,
+            .test_len = noexec_end - noexec_1,
+            .page_ofs = noexec_1 - noexec_2,
+            .entry_ofs = 0,
+            .expected_si_ofs = 0,
+            .expected_pc_ofs = 0,
+            .expected_arg = 0,
+        },
+        {
+            .name = "exrl",
+            .test_code = exrl_1,
+            .test_len = exrl_end - exrl_1,
+            .page_ofs = exrl_1 - exrl_2,
+            .entry_ofs = exrl_1 - exrl_2,
+            .expected_si_ofs = 0,
+            .expected_pc_ofs = exrl_1 - exrl_2,
+            .expected_arg = 0,
+        },
+        {
+            .name = "fallthrough [cross]",
+            .test_code = noexec_1,
+            .test_len = noexec_end - noexec_1,
+            .page_ofs = noexec_1 - noexec_2 - 2,
+            .entry_ofs = noexec_1 - noexec_2 - 2,
+            .expected_si_ofs = 0,
+            .expected_pc_ofs = -2,
+            .expected_arg = 1,
+        },
+        {
+            .name = "jump [cross]",
+            .test_code = noexec_1,
+            .test_len = noexec_end - noexec_1,
+            .page_ofs = noexec_1 - noexec_2 - 2,
+            .entry_ofs = -2,
+            .expected_si_ofs = 0,
+            .expected_pc_ofs = -2,
+            .expected_arg = 0,
+        },
+        {
+            .name = "exrl [cross]",
+            .test_code = exrl_1,
+            .test_len = exrl_end - exrl_1,
+            .page_ofs = exrl_1 - exrl_2 - 2,
+            .entry_ofs = exrl_1 - exrl_2 - 2,
+            .expected_si_ofs = 0,
+            .expected_pc_ofs = exrl_1 - exrl_2 - 2,
+            .expected_arg = 0,
+        },
+    };
+
+    return test_noexec(noexec_tests,
+                       sizeof(noexec_tests) / sizeof(noexec_tests[0]));
+}