cpu: MinorCPU handling IsSquashAfter flag

MinorCPU was not handling IsSquashAfter flagged instructions. The
behaviour was to force a branch (hence enforcing refetching) for
SerializeAfter instructions only. This has now been extended to
SquashAfter in order to correctly support ISB barrier instruction
behaviour.

Change-Id: Ie525b23350b0de121372d3b98b433e36b097d5c4
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5702
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

src/cpu/minor/execute.cc

diff --git a/src/cpu/minor/execute.cc b/src/cpu/minor/execute.cc
index a38a767..7b76ca2 100644
--- a/src/cpu/minor/execute.cc
+++ b/src/cpu/minor/execute.cc
@@ -219,13 +219,14 @@
     const TheISA::PCState &pc_before = inst->pc;
     TheISA::PCState target = thread->pcState();
 
-    /* Force a branch for SerializeAfter instructions at the end of micro-op
-     *  sequence when we're not suspended */
+    /* Force a branch for SerializeAfter/SquashAfter instructions
+     * at the end of micro-op sequence when we're not suspended */
     bool force_branch = thread->status() != ThreadContext::Suspended &&
         !inst->isFault() &&
         inst->isLastOpInInst() &&
         (inst->staticInst->isSerializeAfter() ||
-            inst->staticInst->isIprAccess());
+         inst->staticInst->isSquashAfter() ||
+         inst->staticInst->isIprAccess());
 
     DPRINTF(Branch, "tryToBranch before: %s after: %s%s\n",
         pc_before, target, (force_branch ? " (forcing)" : ""));