target-arm: Add support for generating exceptions with syndrome information

Add new helpers exception_with_syndrome (for generating an exception
with syndrome information) and exception_uncategorized (for generating
an exception with "Unknown or Uncategorized Reason", which have a syndrome
register value of zero), and use them to generate the correct syndrome
information for exceptions which are raised directly from generated code.

This patch includes moving the A32/T32 gen_exception_insn functions
further up in the source file; they will be needed for "VFP/Neon disabled"
exception generation later.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>

1 files changed, 20 insertions, 1 deletions

diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c
index bacfbc0c59..51edd9076c 100644
--- a/target-arm/op_helper.c
+++ b/target-arm/op_helper.c
@@ -244,11 +244,30 @@ void HELPER(wfe)(CPUARMState *env)
     cpu_loop_exit(cs);
 }
 
-void HELPER(exception)(CPUARMState *env, uint32_t excp)
+/* Raise an internal-to-QEMU exception. This is limited to only
+ * those EXCP values which are special cases for QEMU to interrupt
+ * execution and not to be used for exceptions which are passed to
+ * the guest (those must all have syndrome information and thus should
+ * use exception_with_syndrome).
+ */
+void HELPER(exception_internal)(CPUARMState *env, uint32_t excp)
+{
+    CPUState *cs = CPU(arm_env_get_cpu(env));
+
+    assert(excp_is_internal(excp));
+    cs->exception_index = excp;
+    cpu_loop_exit(cs);
+}
+
+/* Raise an exception with the specified syndrome register value */
+void HELPER(exception_with_syndrome)(CPUARMState *env, uint32_t excp,
+                                     uint32_t syndrome)
 {
     CPUState *cs = CPU(arm_env_get_cpu(env));
 
+    assert(!excp_is_internal(excp));
     cs->exception_index = excp;
+    env->exception.syndrome = syndrome;
     cpu_loop_exit(cs);
 }