Initialize PIC register for large PIC model C++ thunk

gcc/

	PR target/63815
	* config/i386/i386.c (ix86_init_large_pic_reg): New.  Extracted
	from ...
	(ix86_init_pic_reg): Here.  Use ix86_init_large_pic_reg.
	(x86_output_mi_thunk): Set PIC register to %r11.  Call
	ix86_init_large_pic_reg to initialize PIC register.

gcc/testsuite/

	PR target/63815
	* g++.dg/other/pr63815.C: New test.

From-SVN: r217445

4 files changed, 96 insertions, 18 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8b98649..1fc374b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2014-11-12  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR target/63815
+	* config/i386/i386.c (ix86_init_large_pic_reg): New.  Extracted
+	from ...
+	(ix86_init_pic_reg): Here.  Use ix86_init_large_pic_reg.
+	(x86_output_mi_thunk): Set PIC register to %r11.  Call
+	ix86_init_large_pic_reg to initialize PIC register.
+
 2014-11-12  Kai Tietz  <ktietz@redhat.com>
 
 	* sdbout.c (sdbout_symbol): Eliminate register only
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 2866900..3d7e057 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -6195,6 +6195,27 @@ ix86_use_pseudo_pic_reg (void)
   return true;
 }
 
+/* Initialize large model PIC register.  */
+
+static void
+ix86_init_large_pic_reg (unsigned int tmp_regno)
+{
+  rtx_code_label *label;
+  rtx tmp_reg;
+
+  gcc_assert (Pmode == DImode);
+  label = gen_label_rtx ();
+  emit_label (label);
+  LABEL_PRESERVE_P (label) = 1;
+  tmp_reg = gen_rtx_REG (Pmode, tmp_regno);
+  gcc_assert (REGNO (pic_offset_table_rtx) != tmp_regno);
+  emit_insn (gen_set_rip_rex64 (pic_offset_table_rtx,
+				label));
+  emit_insn (gen_set_got_offset_rex64 (tmp_reg, label));
+  emit_insn (ix86_gen_add3 (pic_offset_table_rtx,
+			    pic_offset_table_rtx, tmp_reg));
+}
+
 /* Create and initialize PIC register if required.  */
 static void
 ix86_init_pic_reg (void)
@@ -6210,22 +6231,7 @@ ix86_init_pic_reg (void)
   if (TARGET_64BIT)
     {
       if (ix86_cmodel == CM_LARGE_PIC)
-	{
-	  rtx_code_label *label;
-	  rtx tmp_reg;
-
-	  gcc_assert (Pmode == DImode);
-	  label = gen_label_rtx ();
-	  emit_label (label);
-	  LABEL_PRESERVE_P (label) = 1;
-	  tmp_reg = gen_rtx_REG (Pmode, R11_REG);
-	  gcc_assert (REGNO (pic_offset_table_rtx) != REGNO (tmp_reg));
-	  emit_insn (gen_set_rip_rex64 (pic_offset_table_rtx,
-					label));
-	  emit_insn (gen_set_got_offset_rex64 (tmp_reg, label));
-	  emit_insn (ix86_gen_add3 (pic_offset_table_rtx,
-				    pic_offset_table_rtx, tmp_reg));
-	}
+	ix86_init_large_pic_reg (R11_REG);
       else
 	emit_insn (gen_set_got_rex64 (pic_offset_table_rtx));
     }
@@ -42686,8 +42692,16 @@ x86_output_mi_thunk (FILE *file, tree, HOST_WIDE_INT delta,
   else
     {
       if (ix86_cmodel == CM_LARGE_PIC && SYMBOLIC_CONST (fnaddr))
-	fnaddr = legitimize_pic_address (fnaddr,
-					 gen_rtx_REG (Pmode, tmp_regno));
+	{
+	  // CM_LARGE_PIC always uses pseudo PIC register which is
+	  // uninitialized.  Since FUNCTION is local and calling it
+	  // doesn't go through PLT, we use scratch register %r11 as
+	  // PIC register and initialize it here.
+	  SET_REGNO (pic_offset_table_rtx, R11_REG);
+	  ix86_init_large_pic_reg (tmp_regno);
+	  fnaddr = legitimize_pic_address (fnaddr,
+					   gen_rtx_REG (Pmode, tmp_regno));
+	}
 
       if (!sibcall_insn_operand (fnaddr, word_mode))
 	{
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d943df6..93889d4d 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-11-12  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR target/63815
+	* g++.dg/other/pr63815.C: New test.
+
 2014-11-12  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	DR 1510
diff --git a/gcc/testsuite/g++.dg/other/pr63815.C b/gcc/testsuite/g++.dg/other/pr63815.C
new file mode 100644
index 0000000..fce6226
--- /dev/null
+++ b/gcc/testsuite/g++.dg/other/pr63815.C
@@ -0,0 +1,50 @@
+// PR target/63815
+// { dg-do run { target { { i?86-*-linux* x86_64-*-linux* } && lp64 } } }
+// { dg-options "-mcmodel=large" }
+// { dg-additional-options "-fpic" { target fpic } }
+
+struct ICCStringClass
+{
+  virtual int CreateString (int) = 0;
+};
+
+struct AGSCCDynamicObject
+{
+  virtual void Unserialize () = 0;
+};
+
+struct ScriptString:AGSCCDynamicObject, ICCStringClass
+{
+  virtual int CreateString (int);
+  virtual void Unserialize ();
+};
+
+int
+__attribute__ ((noinline))
+CreateNewScriptString (int fromText, bool reAllocate = true)
+{
+  return fromText;
+}
+
+int
+__attribute__ ((noinline))
+ScriptString::CreateString (int fromText)
+{
+  return CreateNewScriptString (fromText);
+}
+
+void
+__attribute__ ((noinline))
+ScriptString::Unserialize ()
+{
+}
+
+int
+main ()
+{
+  ICCStringClass *x = new ScriptString;
+
+  if (x->CreateString (1) != 1)
+    __builtin_abort ();
+  return 0;
+}