* configure.ac: Add --enable-secureplt.

	(HAVE_AS_REL16): Test for R_PPC_REL16 relocs.
	* config.in: Regenerate.
	* configure: Regenerate.
	* config.gcc (powerpc64-*-linux*, powerpc-*-linux*): Add
	rs6000/secureplt.h to tm_file when enable_secureplt.
	* doc/invoke.texi (msecure-plt, mbss-plt): Document.
	* doc/install.texi: Document --enable-targets and --enable-secureplt.
	Correct xrefs to "Using the GNU Compiler Collection (GCC)".
	* config/rs6000/secureplt.h: New file.
	* config/rs6000/sysv4.h (TARGET_SECURE_PLT): Define.
	(SUBTARGET_OVERRIDE_OPTIONS): Error if -msecure-plt given without
	assembler support.
	(CC1_SECURE_PLT_DEFAULT_SPEC): Define.
	(CC1_SPEC): Delete duplicate mno-sdata.  Invoke cc1_secure_plt_default.
	(SUBTARGET_EXTRA_SPECS): Add cc1_secure_plt_default.
	* config/rs6000/sysv4.opt (msecure-plt, bss-plt): Add options.
	* config/rs6000/rs6000.h (TARGET_SECURE_PLT): Define.
	* config/rs6000/rs6000.c (rs6000_emit_load_toc_table): Handle
	TARGET_SECURE_PLT got register load sequence.
	(rs6000_emit_prologue): Call rs6000_emit_load_toc_table when
	TARGET_SECURE_PLT.
	(rs6000_elf_declare_function_name): Don't emit toc address offset
	word when TARGET_SECURE_PLT.
	* config/rs6000/rs6000.md (elf_high, elf_low): Move past load_toc_*.
	(load_toc_v4_PIC_1) Enable for TARGET_SECURE_PLT.
	(load_toc_v4_PIC_3b, load_toc_v4_PIC_3c): New insns.
	(call, call_value): Mark pic_offset_table_rtx used for sysv pic and
	TARGET_SECURE_PLT.
	(call_nonlocal_sysv, call_value_nonlocal_sysv, sibcall_nonlocal_sysv,
	sibcall_value_nonlocal_sysv): Add 32768 offset when TARGET_SECURE_PLT
	and -fPIC.
	* config/rs6000/tramp.asm (trampoline_initial): Use "bcl 20,31".
	(__trampoline_setup): Likewise.  Init r30 before plt call.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@100415 138bc75d-0d04-0410-961f-82ee72b054a4

7 files changed, 217 insertions, 35 deletions

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index b50ab946771..265a9ef402f 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -12572,15 +12572,49 @@ rs6000_emit_load_toc_table (int fromprolog)
   rtx dest, insn;
   dest = gen_rtx_REG (Pmode, RS6000_PIC_OFFSET_TABLE_REGNUM);
 
-  if (TARGET_ELF && DEFAULT_ABI == ABI_V4 && flag_pic == 1)
+  if (TARGET_ELF && TARGET_SECURE_PLT && DEFAULT_ABI != ABI_AIX && flag_pic)
     {
-      rtx temp = (fromprolog
-		  ? gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM)
-		  : gen_reg_rtx (Pmode));
-      insn = emit_insn (gen_load_toc_v4_pic_si (temp));
+      char buf[30];
+      rtx lab, tmp1, tmp2, got, tempLR;
+
+      ASM_GENERATE_INTERNAL_LABEL (buf, "LCF", rs6000_pic_labelno);
+      lab = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (buf));
+      if (flag_pic == 2)
+	got = gen_rtx_SYMBOL_REF (Pmode, toc_label_name);
+      else
+	got = rs6000_got_sym ();
+      tmp1 = tmp2 = dest;
+      if (!fromprolog)
+	{
+	  tmp1 = gen_reg_rtx (Pmode);
+	  tmp2 = gen_reg_rtx (Pmode);
+	}
+      tempLR = (fromprolog
+		? gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM)
+		: gen_reg_rtx (Pmode));
+      insn = emit_insn (gen_load_toc_v4_PIC_1 (tempLR, lab));
+      if (fromprolog)
+	rs6000_maybe_dead (insn);
+      insn = emit_move_insn (tmp1, tempLR);
+      if (fromprolog)
+	rs6000_maybe_dead (insn);
+      insn = emit_insn (gen_load_toc_v4_PIC_3b (tmp2, tmp1, got, lab));
+      if (fromprolog)
+	rs6000_maybe_dead (insn);
+      insn = emit_insn (gen_load_toc_v4_PIC_3c (dest, tmp2, got, lab));
+      if (fromprolog)
+	rs6000_maybe_dead (insn);
+    }
+  else if (TARGET_ELF && DEFAULT_ABI == ABI_V4 && flag_pic == 1)
+    {
+      rtx tempLR = (fromprolog
+		    ? gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM)
+		    : gen_reg_rtx (Pmode));
+
+      insn = emit_insn (gen_load_toc_v4_pic_si (tempLR));
       if (fromprolog)
 	rs6000_maybe_dead (insn);
-      insn = emit_move_insn (dest, temp);
+      insn = emit_move_insn (dest, tempLR);
       if (fromprolog)
 	rs6000_maybe_dead (insn);
     }
@@ -13674,7 +13708,8 @@ rs6000_emit_prologue (void)
 
   /* If we are using RS6000_PIC_OFFSET_TABLE_REGNUM, we need to set it up.  */
   if ((TARGET_TOC && TARGET_MINIMAL_TOC && get_pool_size () != 0)
-      || (DEFAULT_ABI == ABI_V4 && flag_pic == 1
+      || (DEFAULT_ABI == ABI_V4
+	  && (flag_pic == 1 || (flag_pic && TARGET_SECURE_PLT))
 	  && regs_ever_live[RS6000_PIC_OFFSET_TABLE_REGNUM]))
     {
       /* If emit_load_toc_table will use the link register, we need to save
@@ -17204,6 +17239,7 @@ rs6000_elf_declare_function_name (FILE *file, const char *name, tree decl)
     }
 
   if (TARGET_RELOCATABLE
+      && !TARGET_SECURE_PLT
       && (get_pool_size () != 0 || current_function_profile)
       && uses_TOC ())
     {
diff --git a/gcc/config/rs6000/rs6000.h b/gcc/config/rs6000/rs6000.h
index 79fcc68c3cb..2710dad4dae 100644
--- a/gcc/config/rs6000/rs6000.h
+++ b/gcc/config/rs6000/rs6000.h
@@ -144,6 +144,10 @@
 #define TARGET_POPCNTB 0
 #endif
 
+#ifndef TARGET_SECURE_PLT
+#define TARGET_SECURE_PLT 0
+#endif
+
 #define TARGET_32BIT		(! TARGET_64BIT)
 
 /* Emit a dtp-relative reference to a TLS variable.  */
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index d46f97db899..02847df7c2f 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -7360,26 +7360,6 @@
 
 ;; Now define ways of moving data around.
 
-;; Elf specific ways of loading addresses for non-PIC code.
-;; The output of this could be r0, but we make a very strong
-;; preference for a base register because it will usually
-;; be needed there.
-(define_insn "elf_high"
-  [(set (match_operand:SI 0 "gpc_reg_operand" "=b*r")
-	(high:SI (match_operand 1 "" "")))]
-  "TARGET_ELF && ! TARGET_64BIT"
-  "{liu|lis} %0,%1@ha")
-
-(define_insn "elf_low"
-  [(set (match_operand:SI 0 "gpc_reg_operand" "=r,r")
-	(lo_sum:SI (match_operand:SI 1 "gpc_reg_operand" "b,!*r")
-		   (match_operand 2 "" "")))]
-   "TARGET_ELF && ! TARGET_64BIT"
-   "@
-    {cal|la} %0,%2@l(%1)
-    {ai|addic} %0,%1,%K2")
-
-
 ;; Set up a register with a value from the GOT table
 
 (define_expand "movsi_got"
@@ -9810,7 +9790,8 @@
   [(set (match_operand:SI 0 "register_operand" "=l")
 	(match_operand:SI 1 "immediate_operand" "s"))
    (use (unspec [(match_dup 1)] UNSPEC_TOC))]
-  "TARGET_ELF && DEFAULT_ABI != ABI_AIX && flag_pic == 2"
+  "TARGET_ELF && DEFAULT_ABI != ABI_AIX
+   && (flag_pic == 2 || (flag_pic && TARGET_SECURE_PLT))"
   "bcl 20,31,%1\\n%1:"
   [(set_attr "type" "branch")
    (set_attr "length" "4")])
@@ -9833,6 +9814,22 @@
   "{l|lwz} %0,%2-%3(%1)"
   [(set_attr "type" "load")])
 
+(define_insn "load_toc_v4_PIC_3b"
+  [(set (match_operand:SI 0 "gpc_reg_operand" "=b")
+	(plus:SI (match_operand:SI 1 "gpc_reg_operand" "r")
+		 (high:SI
+		   (minus:SI (match_operand:SI 2 "symbol_ref_operand" "s")
+			     (match_operand:SI 3 "symbol_ref_operand" "s")))))]
+  "TARGET_ELF && TARGET_SECURE_PLT && DEFAULT_ABI != ABI_AIX && flag_pic"
+  "{cau|addis} %0,%1,%2-%3@ha")
+
+(define_insn "load_toc_v4_PIC_3c"
+  [(set (match_operand:SI 0 "gpc_reg_operand" "=r")
+	(lo_sum:SI (match_operand:SI 1 "gpc_reg_operand" "b")
+		   (minus:SI (match_operand:SI 2 "symbol_ref_operand" "s")
+			     (match_operand:SI 3 "symbol_ref_operand" "s"))))]
+  "TARGET_ELF && TARGET_SECURE_PLT && DEFAULT_ABI != ABI_AIX && flag_pic"
+  "{cal|addi} %0,%1,%2-%3@l")
 
 ;; If the TOC is shared over a translation unit, as happens with all
 ;; the kinds of PIC that we support, we need to restore the TOC
@@ -9867,6 +9864,25 @@
     rs6000_emit_load_toc_table (FALSE);
   DONE;
 }")
+
+;; Elf specific ways of loading addresses for non-PIC code.
+;; The output of this could be r0, but we make a very strong
+;; preference for a base register because it will usually
+;; be needed there.
+(define_insn "elf_high"
+  [(set (match_operand:SI 0 "gpc_reg_operand" "=b*r")
+	(high:SI (match_operand 1 "" "")))]
+  "TARGET_ELF && ! TARGET_64BIT"
+  "{liu|lis} %0,%1@ha")
+
+(define_insn "elf_low"
+  [(set (match_operand:SI 0 "gpc_reg_operand" "=r,r")
+	(lo_sum:SI (match_operand:SI 1 "gpc_reg_operand" "b,!*r")
+		   (match_operand 2 "" "")))]
+   "TARGET_ELF && ! TARGET_64BIT"
+   "@
+    {cal|la} %0,%2@l(%1)
+    {ai|addic} %0,%1,%K2")
 
 ;; A function pointer under AIX is a pointer to a data area whose first word
 ;; contains the actual address of the function, whose second word contains a
@@ -9983,6 +9999,25 @@
 
   operands[0] = XEXP (operands[0], 0);
 
+  if (DEFAULT_ABI == ABI_V4 && TARGET_SECURE_PLT
+      && flag_pic
+      && GET_CODE (operands[0]) == SYMBOL_REF
+      && !SYMBOL_REF_LOCAL_P (operands[0]))
+    {
+      rtx call;
+      rtvec tmp;
+
+      tmp = gen_rtvec (3,
+		       gen_rtx_CALL (VOIDmode,
+				     gen_rtx_MEM (SImode, operands[0]),
+				     operands[1]),
+		       gen_rtx_USE (VOIDmode, operands[2]),
+		       gen_rtx_CLOBBER (VOIDmode, gen_rtx_SCRATCH (SImode)));
+      call = emit_call_insn (gen_rtx_PARALLEL (VOIDmode, tmp));
+      use_reg (&CALL_INSN_FUNCTION_USAGE (call), pic_offset_table_rtx);
+      DONE;
+    }
+
   if (GET_CODE (operands[0]) != SYMBOL_REF
       || (DEFAULT_ABI == ABI_AIX && !SYMBOL_REF_FUNCTION_P (operands[0]))
       || (DEFAULT_ABI != ABI_DARWIN && (INTVAL (operands[2]) & CALL_LONG) != 0))
@@ -10034,6 +10069,28 @@
 
   operands[1] = XEXP (operands[1], 0);
 
+  if (DEFAULT_ABI == ABI_V4 && TARGET_SECURE_PLT
+      && flag_pic
+      && GET_CODE (operands[1]) == SYMBOL_REF
+      && !SYMBOL_REF_LOCAL_P (operands[1]))
+    {
+      rtx call;
+      rtvec tmp;
+
+      tmp = gen_rtvec (3,
+		       gen_rtx_SET (VOIDmode,
+				    operands[0],
+				    gen_rtx_CALL (VOIDmode,
+						  gen_rtx_MEM (SImode,
+							       operands[1]),
+						  operands[2])),
+		       gen_rtx_USE (VOIDmode, operands[3]),
+		       gen_rtx_CLOBBER (VOIDmode, gen_rtx_SCRATCH (SImode)));
+      call = emit_call_insn (gen_rtx_PARALLEL (VOIDmode, tmp));
+      use_reg (&CALL_INSN_FUNCTION_USAGE (call), pic_offset_table_rtx);
+      DONE;
+    }
+
   if (GET_CODE (operands[1]) != SYMBOL_REF
       || (DEFAULT_ABI == ABI_AIX && !SYMBOL_REF_FUNCTION_P (operands[1]))
       || (DEFAULT_ABI != ABI_DARWIN && (INTVAL (operands[3]) & CALL_LONG) != 0))
@@ -10307,7 +10364,18 @@
 #if TARGET_MACHO
   return output_call(insn, operands, 0, 2);
 #else
-  return (DEFAULT_ABI == ABI_V4 && flag_pic) ? "bl %z0@plt" : "bl %z0";
+  if (DEFAULT_ABI == ABI_V4 && flag_pic)
+    {
+      if (TARGET_SECURE_PLT && flag_pic == 2)
+	/* The magic 32768 offset here and in the other sysv call insns
+	   corresponds to the offset of r30 in .got2, as given by LCTOC1.
+	   See sysv4.h:toc_section.  */
+	return "bl %z0+32768@plt";
+      else
+	return "bl %z0@plt";
+    }
+  else
+    return "bl %z0";
 #endif
 }
   [(set_attr "type" "branch,branch")
@@ -10352,7 +10420,15 @@
 #if TARGET_MACHO
   return output_call(insn, operands, 1, 3);
 #else
-  return (DEFAULT_ABI == ABI_V4 && flag_pic) ? "bl %z1@plt" : "bl %z1";
+  if (DEFAULT_ABI == ABI_V4 && flag_pic)
+    {
+      if (TARGET_SECURE_PLT && flag_pic == 2)
+	return "bl %z1+32768@plt";
+      else
+	return "bl %z1@plt";
+    }
+  else
+    return "bl %z1";
 #endif
 }
   [(set_attr "type" "branch,branch")
@@ -10567,7 +10643,15 @@
   else if (INTVAL (operands[2]) & CALL_V4_CLEAR_FP_ARGS)
     output_asm_insn (\"creqv 6,6,6\", operands);
 
-  return (DEFAULT_ABI == ABI_V4 && flag_pic) ? \"b %z0@plt\" : \"b %z0\";
+  if (DEFAULT_ABI == ABI_V4 && flag_pic)
+    {
+      if (TARGET_SECURE_PLT && flag_pic == 2)
+	return \"b %z0+32768@plt\";
+      else
+	return \"b %z0@plt\";
+    }
+  else
+    return \"b %z0\";
 }"
   [(set_attr "type" "branch,branch")
    (set_attr "length" "4,8")])
@@ -10613,7 +10697,15 @@
   else if (INTVAL (operands[2]) & CALL_V4_CLEAR_FP_ARGS)
     output_asm_insn (\"creqv 6,6,6\", operands);
 
-  return (DEFAULT_ABI == ABI_V4 && flag_pic) ? \"b %z1@plt\" : \"b %z1\";
+  if (DEFAULT_ABI == ABI_V4 && flag_pic)
+    {
+      if (TARGET_SECURE_PLT && flag_pic == 2)
+	return \"b %z1+32768@plt\";
+      else
+	return \"b %z1@plt\";
+    }
+  else
+    return \"b %z1\";
 }"
   [(set_attr "type" "branch,branch")
    (set_attr "length" "4,8")])
diff --git a/gcc/config/rs6000/secureplt.h b/gcc/config/rs6000/secureplt.h
new file mode 100644
index 00000000000..91aea5634bb
--- /dev/null
+++ b/gcc/config/rs6000/secureplt.h
@@ -0,0 +1,21 @@
+/* Default to -msecure-plt.
+   Copyright (C) 2005 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GCC 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING.  If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#define CC1_SECURE_PLT_DEFAULT_SPEC "-msecure-plt"
diff --git a/gcc/config/rs6000/sysv4.h b/gcc/config/rs6000/sysv4.h
index a8b06aedb16..ed5deb1a55e 100644
--- a/gcc/config/rs6000/sysv4.h
+++ b/gcc/config/rs6000/sysv4.h
@@ -59,6 +59,11 @@ extern enum rs6000_sdata_type rs6000_sdata;
 #define	TARGET_NO_TOC		(! TARGET_TOC)
 #define	TARGET_NO_EABI		(! TARGET_EABI)
 
+#ifdef HAVE_AS_REL16
+#undef TARGET_SECURE_PLT
+#define TARGET_SECURE_PLT	secure_plt
+#endif
+
 extern const char *rs6000_abi_name;
 extern const char *rs6000_sdata_name;
 extern const char *rs6000_tls_size_string; /* For -mtls-size= */
@@ -205,6 +210,11 @@ do {									\
       error ("-mcall-aixdesc must be big endian");			\
     }									\
 									\
+  if (TARGET_SECURE_PLT != secure_plt)					\
+    {									\
+      error ("-msecure-plt not supported by your assembler");		\
+    }									\
+									\
   /* Treat -fPIC the same as -mrelocatable.  */				\
   if (flag_pic > 1 && DEFAULT_ABI != ABI_AIX)				\
     target_flags |= MASK_RELOCATABLE | MASK_MINIMAL_TOC | MASK_NO_FP_IN_TOC; \
@@ -750,6 +760,10 @@ extern int fixuplabelno;
 
 #define	CC1_ENDIAN_DEFAULT_SPEC "%(cc1_endian_big)"
 
+#ifndef CC1_SECURE_PLT_DEFAULT_SPEC
+#define CC1_SECURE_PLT_DEFAULT_SPEC ""
+#endif
+
 /* Pass -G xxx to the compiler and set correct endian mode.  */
 #define	CC1_SPEC "%{G*} \
 %{mlittle|mlittle-endian: %(cc1_endian_little);           \
@@ -762,7 +776,6 @@ extern int fixuplabelno;
   mcall-gnu             : -mbig %(cc1_endian_big);        \
   mcall-i960-old        : -mlittle %(cc1_endian_little);  \
                         : %(cc1_endian_default)}          \
-%{mno-sdata: -msdata=none } \
 %{meabi: %{!mcall-*: -mcall-sysv }} \
 %{!meabi: %{!mno-eabi: \
     %{mrelocatable: -meabi } \
@@ -774,6 +787,7 @@ extern int fixuplabelno;
     %{mcall-openbsd: -mno-eabi }}} \
 %{msdata: -msdata=default} \
 %{mno-sdata: -msdata=none} \
+%{!mbss-plt: %{!msecure-plt: %(cc1_secure_plt_default)}} \
 %{profile: -p}"
 
 /* Don't put -Y P,<path> for cross compilers.  */
@@ -1214,6 +1228,7 @@ ncrtn.o%s"
   { "cc1_endian_big",		CC1_ENDIAN_BIG_SPEC },			\
   { "cc1_endian_little",	CC1_ENDIAN_LITTLE_SPEC },		\
   { "cc1_endian_default",	CC1_ENDIAN_DEFAULT_SPEC },		\
+  { "cc1_secure_plt_default",	CC1_SECURE_PLT_DEFAULT_SPEC },		\
   { "cpp_os_ads",		CPP_OS_ADS_SPEC },			\
   { "cpp_os_yellowknife",	CPP_OS_YELLOWKNIFE_SPEC },		\
   { "cpp_os_mvme",		CPP_OS_MVME_SPEC },			\
diff --git a/gcc/config/rs6000/sysv4.opt b/gcc/config/rs6000/sysv4.opt
index d826c55dd72..289c6e19e21 100644
--- a/gcc/config/rs6000/sysv4.opt
+++ b/gcc/config/rs6000/sysv4.opt
@@ -139,3 +139,11 @@ Generate 32-bit code
 mnewlib
 Target RejectNegative
 no description yet
+
+msecure-plt
+Target Report RejectNegative Var(secure_plt, 1)
+Generate code to use a non-exec PLT and GOT
+
+mbss-plt
+Target Report RejectNegative Var(secure_plt, 0)
+Generate code for old exec BSS PLT
diff --git a/gcc/config/rs6000/tramp.asm b/gcc/config/rs6000/tramp.asm
index 284f9386074..0c6127d567b 100644
--- a/gcc/config/rs6000/tramp.asm
+++ b/gcc/config/rs6000/tramp.asm
@@ -44,7 +44,7 @@
 	.align	2
 trampoline_initial:
 	mflr	r0
-	bl	1f
+	bcl	20,31,1f
 .Lfunc = .-trampoline_initial
 	.long	0			/* will be replaced with function address */
 .Lchain = .-trampoline_initial
@@ -67,7 +67,7 @@ trampoline_size = .-trampoline_initial
 
 FUNC_START(__trampoline_setup)
 	mflr	r0		/* save return address */
-        bl	.LCF0		/* load up __trampoline_initial into r7 */
+        bcl	20,31,.LCF0	/* load up __trampoline_initial into r7 */
 .LCF0:
         mflr	r11
         addi	r7,r11,trampoline_initial-4-.LCF0 /* trampoline address -4 */
@@ -105,6 +105,12 @@ FUNC_START(__trampoline_setup)
 	blr
 
 .Labort:
+#if defined SHARED && defined HAVE_AS_REL16
+	bcl	20,31,1f
+1:	mflr	r30
+	addis	r30,r30,_GLOBAL_OFFSET_TABLE_-1b@ha
+	addi	r30,r30,_GLOBAL_OFFSET_TABLE_-1b@l
+#endif
 	bl	JUMP_TARGET(abort)
 FUNC_END(__trampoline_setup)