[PATCH 4/7] [ARC] Use TARGET_USE_ANCHORS_FOR_SYMBOL_P.

[Claudiu Zissulescu]

From: Claudiu Zissulescu <claz...@gmail.com>

We don't want to use anchors for small data: the GP register acts as an anchor 
in that
case.  We also don't want to use them for PC-relative accesses,
where the PC acts as an anchor.  TLS symbols require special accesses as well, 
don't use
anchors for such symbols.

gcc/
2017-04-28  Claudiu Zissulescu  <claz...@synopsys.com>

        * config/arc/arc.c (arc_use_anchors_for_symbol_p): New function.
        (TARGET_USE_ANCHORS_FOR_SYMBOL_P): Define.

gcc/testsuite
2017-04-28  Claudiu Zissulescu  <claz...@synopsys.com>

        * gcc.target/arc/pr9001184797.c: New test.
---
 gcc/config/arc/arc.c                        | 24 ++++++++++++++++++++++++
 gcc/testsuite/gcc.target/arc/pr9001184797.c | 19 +++++++++++++++++++
 2 files changed, 43 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/arc/pr9001184797.c

diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c
index 3980a0f..c94b187 100644
--- a/gcc/config/arc/arc.c
+++ b/gcc/config/arc/arc.c
@@ -10687,6 +10687,30 @@ arc_builtin_setjmp_frame_value (void)
   return gen_raw_REG (Pmode, FRAME_POINTER_REGNUM);
 }
 
+/* Implement TARGET_USE_ANCHORS_FOR_SYMBOL_P.  We don't want to use
+   anchors for small data: the GP register acts as an anchor in that
+   case.  We also don't want to use them for PC-relative accesses,
+   where the PC acts as an anchor.  Prohibit also TLS symbols to use
+   anchors.  */
+
+static bool
+arc_use_anchors_for_symbol_p (const_rtx symbol)
+{
+  if (SYMBOL_REF_TLS_MODEL (symbol))
+    return false;
+
+  if (flag_pic)
+    return false;
+
+  if (SYMBOL_REF_SMALL_P (symbol))
+    return false;
+
+  return default_use_anchors_for_symbol_p (symbol);
+}
+
+#undef TARGET_USE_ANCHORS_FOR_SYMBOL_P
+#define TARGET_USE_ANCHORS_FOR_SYMBOL_P arc_use_anchors_for_symbol_p
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 #include "gt-arc.h"
diff --git a/gcc/testsuite/gcc.target/arc/pr9001184797.c 
b/gcc/testsuite/gcc.target/arc/pr9001184797.c
new file mode 100644
index 0000000..e76c676
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arc/pr9001184797.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target tls } */
+/* { dg-options "-Os -w -mno-ll64" } */
+
+/* This test studies the use of anchors and tls symbols. */
+
+struct a b;
+struct a {
+  long c;
+  long d
+} e() {
+  static __thread struct a f;
+  static __thread g;
+  g = 5;
+  h();
+  if (f.c)
+    g = g & 5;
+  f = b;
+}
-- 
1.9.1