tests/tcg: Add arm and aarch64 pc alignment tests

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 50 insertions, 0 deletions

diff --git a/tests/tcg/arm/Makefile.target b/tests/tcg/arm/Makefile.target
index 5ab59ed6ce..f509d823d4 100644
--- a/tests/tcg/arm/Makefile.target
+++ b/tests/tcg/arm/Makefile.target
@@ -29,6 +29,10 @@ run-fcvt: fcvt
 	$(call run-test,fcvt,$(QEMU) $<,"$< on $(TARGET_NAME)")
 	$(call diff-out,fcvt,$(ARM_SRC)/fcvt.ref)
 
+# PC alignment test
+ARM_TESTS += pcalign-a32
+pcalign-a32: CFLAGS+=-marm
+
 ifeq ($(CONFIG_ARM_COMPATIBLE_SEMIHOSTING),y)
 
 # Semihosting smoke test for linux-user
diff --git a/tests/tcg/arm/pcalign-a32.c b/tests/tcg/arm/pcalign-a32.c
new file mode 100644
index 0000000000..3c9c8cc97b
--- /dev/null
+++ b/tests/tcg/arm/pcalign-a32.c
@@ -0,0 +1,46 @@
+/* Test PC misalignment exception */
+
+#ifdef __thumb__
+#error "This test must be compiled for ARM"
+#endif
+
+#include <assert.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+static void *expected;
+
+static void sigbus(int sig, siginfo_t *info, void *vuc)
+{
+    assert(info->si_code == BUS_ADRALN);
+    assert(info->si_addr == expected);
+    exit(EXIT_SUCCESS);
+}
+
+int main()
+{
+    void *tmp;
+
+    struct sigaction sa = {
+        .sa_sigaction = sigbus,
+        .sa_flags = SA_SIGINFO
+    };
+
+    if (sigaction(SIGBUS, &sa, NULL) < 0) {
+        perror("sigaction");
+        return EXIT_FAILURE;
+    }
+
+    asm volatile("adr %0, 1f + 2\n\t"
+                 "str %0, %1\n\t"
+                 "bx  %0\n"
+                 "1:"
+                 : "=&r"(tmp), "=m"(expected));
+
+    /*
+     * From v8, it is CONSTRAINED UNPREDICTABLE whether BXWritePC aligns
+     * the address or not.  If so, we can legitimately fall through.
+     */
+    return EXIT_SUCCESS;
+}