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>

tests/tcg/aarch64/Makefile.target

@@ -8,8 +8,8 @@ VPATH 		+= $(ARM_SRC)
 AARCH64_SRC=$(SRC_PATH)/tests/tcg/aarch64
 VPATH 		+= $(AARCH64_SRC)
 
-# Float-convert Tests
-AARCH64_TESTS=fcvt
+# Base architecture tests
+AARCH64_TESTS=fcvt pcalign-a64
 
 fcvt: LDFLAGS+=-lm
 

tests/tcg/aarch64/pcalign-a64.c

@@ -0,0 +1,37 @@
+/* Test PC misalignment exception */
+
+#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 + 1\n\t"
+                 "str %0, %1\n\t"
+                 "br  %0\n"
+                 "1:"
+                 : "=&r"(tmp), "=m"(expected));
+    abort();
+}

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

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;
+}