1 files changed, 78 insertions, 0 deletions
diff --git a/target/arm/sve_helper.c b/target/arm/sve_helper.c
new file mode 100644
index 0000000..1ebb67e
--- /dev/null
+++ b/target/arm/sve_helper.c
@@ -0,0 +1,78 @@
+/*
+ * ARM SVE Operations
+ *
+ * Copyright (c) 2018 Linaro, Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "exec/exec-all.h"
+#include "exec/cpu_ldst.h"
+#include "exec/helper-proto.h"
+#include "tcg/tcg-gvec-desc.h"
+
+
+/* Return a value for NZCV as per the ARM PredTest pseudofunction.
+ *
+ * The return value has bit 31 set if N is set, bit 1 set if Z is clear,
+ * and bit 0 set if C is set.  Compare the definitions of these variables
+ * within CPUARMState.
+ */
+
+/* For no G bits set, NZCV = C.  */
+#define PREDTEST_INIT  1
+
+/* This is an iterative function, called for each Pd and Pg word
+ * moving forward.
+ */
+static uint32_t iter_predtest_fwd(uint64_t d, uint64_t g, uint32_t flags)
+{
+    if (likely(g)) {
+        /* Compute N from first D & G.
+           Use bit 2 to signal first G bit seen.  */
+        if (!(flags & 4)) {
+            flags |= ((d & (g & -g)) != 0) << 31;
+            flags |= 4;
+        }
+
+        /* Accumulate Z from each D & G.  */
+        flags |= ((d & g) != 0) << 1;
+
+        /* Compute C from last !(D & G).  Replace previous.  */
+        flags = deposit32(flags, 0, 1, (d & pow2floor(g)) == 0);
+    }
+    return flags;
+}
+
+/* The same for a single word predicate.  */
+uint32_t HELPER(sve_predtest1)(uint64_t d, uint64_t g)
+{
+    return iter_predtest_fwd(d, g, PREDTEST_INIT);
+}
+
+/* The same for a multi-word predicate.  */
+uint32_t HELPER(sve_predtest)(void *vd, void *vg, uint32_t words)
+{
+    uint32_t flags = PREDTEST_INIT;
+    uint64_t *d = vd, *g = vg;
+    uintptr_t i = 0;
+
+    do {
+        flags = iter_predtest_fwd(d[i], g[i], flags);
+    } while (++i < words);
+
+    return flags;
+}