Revert "[ARM] Fix PR85434: spilling of stack protector guard's address on ARM"

This reverts commit r263245.

From-SVN: r263252

4 files changed, 17 insertions, 136 deletions

diff --git a/gcc/config/arm/arm-protos.h b/gcc/config/arm/arm-protos.h
index 100844e..8537262 100644
--- a/gcc/config/arm/arm-protos.h
+++ b/gcc/config/arm/arm-protos.h
@@ -67,7 +67,7 @@ extern int const_ok_for_dimode_op (HOST_WIDE_INT, enum rtx_code);
 extern int arm_split_constant (RTX_CODE, machine_mode, rtx,
 			       HOST_WIDE_INT, rtx, rtx, int);
 extern int legitimate_pic_operand_p (rtx);
-extern rtx legitimize_pic_address (rtx, machine_mode, rtx, rtx, bool);
+extern rtx legitimize_pic_address (rtx, machine_mode, rtx);
 extern rtx legitimize_tls_address (rtx, rtx);
 extern bool arm_legitimate_address_p (machine_mode, rtx, bool);
 extern int arm_legitimate_address_outer_p (machine_mode, rtx, RTX_CODE, int);
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 87c728e..f5eece4 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -7369,26 +7369,20 @@ legitimate_pic_operand_p (rtx x)
 }
 
 /* Record that the current function needs a PIC register.  Initialize
-   cfun->machine->pic_reg if we have not already done so.
-
-   A new pseudo register is used for the PIC register if possible, otherwise
-   PIC_REG must be non NULL and is used instead.  COMPUTE_NOW forces the PIC
-   register to be loaded, irregardless of whether it was loaded previously.  */
+   cfun->machine->pic_reg if we have not already done so.  */
 
 static void
-require_pic_register (rtx pic_reg, bool compute_now)
+require_pic_register (void)
 {
   /* A lot of the logic here is made obscure by the fact that this
      routine gets called as part of the rtx cost estimation process.
      We don't want those calls to affect any assumptions about the real
      function; and further, we can't call entry_of_function() until we
      start the real expansion process.  */
-  if (!crtl->uses_pic_offset_table || compute_now)
+  if (!crtl->uses_pic_offset_table)
     {
-      gcc_assert (can_create_pseudo_p ()
-		  || (pic_reg != NULL_RTX && GET_MODE (pic_reg) == Pmode));
+      gcc_assert (can_create_pseudo_p ());
       if (arm_pic_register != INVALID_REGNUM
-	  && can_create_pseudo_p ()
 	  && !(TARGET_THUMB1 && arm_pic_register > LAST_LO_REGNUM))
 	{
 	  if (!cfun->machine->pic_reg)
@@ -7405,8 +7399,7 @@ require_pic_register (rtx pic_reg, bool compute_now)
 	  rtx_insn *seq, *insn;
 
 	  if (!cfun->machine->pic_reg)
-	    cfun->machine->pic_reg =
-	      can_create_pseudo_p () ? gen_reg_rtx (Pmode) : pic_reg;
+	    cfun->machine->pic_reg = gen_reg_rtx (Pmode);
 
 	  /* Play games to avoid marking the function as needing pic
 	     if we are being called as part of the cost-estimation
@@ -7417,8 +7410,7 @@ require_pic_register (rtx pic_reg, bool compute_now)
 	      start_sequence ();
 
 	      if (TARGET_THUMB1 && arm_pic_register != INVALID_REGNUM
-		  && arm_pic_register > LAST_LO_REGNUM
-		  && can_create_pseudo_p ())
+		  && arm_pic_register > LAST_LO_REGNUM)
 		emit_move_insn (cfun->machine->pic_reg,
 				gen_rtx_REG (Pmode, arm_pic_register));
 	      else
@@ -7435,29 +7427,15 @@ require_pic_register (rtx pic_reg, bool compute_now)
 	         we can't yet emit instructions directly in the final
 		 insn stream.  Queue the insns on the entry edge, they will
 		 be committed after everything else is expanded.  */
-	      if (currently_expanding_to_rtl)
-		insert_insn_on_edge (seq,
-				     single_succ_edge
-				     (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
-	      else
-		emit_insn (seq);
+	      insert_insn_on_edge (seq,
+				   single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
 	    }
 	}
     }
 }
 
-/* Legitimize PIC load to ORIG into REG.  If REG is NULL, a new pseudo is
-   created to hold the result of the load.  If not NULL, PIC_REG indicates
-   which register to use as PIC register, otherwise it is decided by register
-   allocator.  COMPUTE_NOW forces the PIC register to be loaded at the current
-   location in the instruction stream, irregardless of whether it was loaded
-   previously.
-
-   Returns the register REG into which the PIC load is performed.  */
-
 rtx
-legitimize_pic_address (rtx orig, machine_mode mode, rtx reg, rtx pic_reg,
-			bool compute_now)
+legitimize_pic_address (rtx orig, machine_mode mode, rtx reg)
 {
   if (GET_CODE (orig) == SYMBOL_REF
       || GET_CODE (orig) == LABEL_REF)
@@ -7491,7 +7469,7 @@ legitimize_pic_address (rtx orig, machine_mode mode, rtx reg, rtx pic_reg,
 	  rtx mem;
 
 	  /* If this function doesn't have a pic register, create one now.  */
-	  require_pic_register (pic_reg, compute_now);
+	  require_pic_register ();
 
 	  pat = gen_calculate_pic_address (reg, cfun->machine->pic_reg, orig);
 
@@ -7542,11 +7520,9 @@ legitimize_pic_address (rtx orig, machine_mode mode, rtx reg, rtx pic_reg,
 
       gcc_assert (GET_CODE (XEXP (orig, 0)) == PLUS);
 
-      base = legitimize_pic_address (XEXP (XEXP (orig, 0), 0), Pmode, reg,
-				     pic_reg, compute_now);
+      base = legitimize_pic_address (XEXP (XEXP (orig, 0), 0), Pmode, reg);
       offset = legitimize_pic_address (XEXP (XEXP (orig, 0), 1), Pmode,
-				       base == reg ? 0 : reg, pic_reg,
-				       compute_now);
+				       base == reg ? 0 : reg);
 
       if (CONST_INT_P (offset))
 	{
@@ -8731,8 +8707,7 @@ arm_legitimize_address (rtx x, rtx orig_x, machine_mode mode)
     {
       /* We need to find and carefully transform any SYMBOL and LABEL
 	 references; so go back to the original address expression.  */
-      rtx new_x = legitimize_pic_address (orig_x, mode, NULL_RTX, NULL_RTX,
-					  false /*compute_now*/);
+      rtx new_x = legitimize_pic_address (orig_x, mode, NULL_RTX);
 
       if (new_x != orig_x)
 	x = new_x;
@@ -8800,8 +8775,7 @@ thumb_legitimize_address (rtx x, rtx orig_x, machine_mode mode)
     {
       /* We need to find and carefully transform any SYMBOL and LABEL
 	 references; so go back to the original address expression.  */
-      rtx new_x = legitimize_pic_address (orig_x, mode, NULL_RTX, NULL_RTX,
-					  false /*compute_now*/);
+      rtx new_x = legitimize_pic_address (orig_x, mode, NULL_RTX);
 
       if (new_x != orig_x)
 	x = new_x;
@@ -18085,7 +18059,7 @@ arm_emit_call_insn (rtx pat, rtx addr, bool sibcall)
 	  ? !targetm.binds_local_p (SYMBOL_REF_DECL (addr))
 	  : !SYMBOL_REF_LOCAL_P (addr)))
     {
-      require_pic_register (NULL_RTX, false /*compute_now*/);
+      require_pic_register ();
       use_reg (&CALL_INSN_FUNCTION_USAGE (insn), cfun->machine->pic_reg);
     }
 
diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md
index 130531d..ca2a2f5 100644
--- a/gcc/config/arm/arm.md
+++ b/gcc/config/arm/arm.md
@@ -6021,8 +6021,7 @@
       operands[1] = legitimize_pic_address (operands[1], SImode,
 					    (!can_create_pseudo_p ()
 					     ? operands[0]
-					     : NULL_RTX), NULL_RTX,
-					    false /*compute_now*/);
+					     : 0));
   }
   "
 )
@@ -8635,95 +8634,6 @@
    (set_attr "conds" "clob")]
 )
 
-;; Named patterns for stack smashing protection.
-(define_insn_and_split "stack_protect_combined_set"
-  [(set (match_operand:SI 0 "memory_operand" "=m")
-	(unspec:SI [(match_operand:SI 1 "memory_operand" "X")]
-		   UNSPEC_SP_SET))
-   (match_scratch:SI 2 "=r")
-   (match_scratch:SI 3 "=r")]
-  ""
-  "#"
-  "reload_completed"
-  [(parallel [(set (match_dup 0) (unspec:SI [(mem:SI (match_dup 2))]
-					    UNSPEC_SP_SET))
-	      (clobber (match_dup 2))])]
-  "
-{
-  rtx addr = XEXP (operands[1], 0);
-  if (flag_pic)
-    {
-      /* Forces recomputing of GOT base now.  */
-      operands[1] = legitimize_pic_address (addr, SImode, operands[2],
-					    operands[3], true /*compute_now*/);
-    }
-  else
-    {
-      if (!address_operand (addr, SImode))
-	operands[1] = force_const_mem (SImode, addr);
-      emit_move_insn (operands[2], operands[1]);
-    }
-}"
-)
-
-(define_insn "stack_protect_set"
-  [(set (match_operand:SI 0 "memory_operand" "=m")
-	(unspec:SI [(mem:SI (match_operand:SI 1 "register_operand" "r"))]
-	 UNSPEC_SP_SET))
-   (clobber (match_dup 1))]
-  ""
-  "ldr\\t%1, [%1]\;str\\t%1, %0\;mov\t%1,0"
-  [(set_attr "length" "12")
-   (set_attr "type" "multiple")])
-
-(define_insn_and_split "stack_protect_combined_test"
-  [(set (pc)
-	(if_then_else
-		(eq (match_operand:SI 0 "memory_operand" "m")
-		    (unspec:SI [(match_operand:SI 1 "memory_operand" "X")]
-			       UNSPEC_SP_TEST))
-		(label_ref (match_operand 2))
-		(pc)))
-   (match_scratch:SI 3 "=r")
-   (match_scratch:SI 4 "=r")]
-  ""
-  "#"
-  "reload_completed"
-  [(const_int 0)]
-{
-  rtx eq, addr;
-
-  addr = XEXP (operands[1], 0);
-  if (flag_pic)
-    {
-      /* Forces recomputing of GOT base now.  */
-      operands[1] = legitimize_pic_address (addr, SImode, operands[3],
-					    operands[4],
-					    true /*compute_now*/);
-    }
-  else
-    {
-      if (!address_operand (addr, SImode))
-	operands[1] = force_const_mem (SImode, addr);
-      emit_move_insn (operands[3], operands[1]);
-    }
-  emit_insn (gen_stack_protect_test (operands[4], operands[0], operands[3]));
-  eq = gen_rtx_EQ (VOIDmode, operands[4], const0_rtx);
-  emit_jump_insn (gen_cbranchsi4 (eq, operands[4], const0_rtx, operands[2]));
-  DONE;
-})
-
-(define_insn "stack_protect_test"
-  [(set (match_operand:SI 0 "register_operand" "=r")
-	(unspec:SI [(match_operand:SI 1 "memory_operand" "m")
-		    (mem:SI (match_operand:SI 2 "register_operand" "r"))]
-	 UNSPEC_SP_TEST))
-   (clobber (match_dup 2))]
-  ""
-  "ldr\t%0, [%2]\;ldr\t%2, %1\;eor\t%0, %2, %0"
-  [(set_attr "length" "12")
-   (set_attr "type" "multiple")])
-
 (define_expand "casesi"
   [(match_operand:SI 0 "s_register_operand" "")	; index to jump on
    (match_operand:SI 1 "const_int_operand" "")	; lower bound
diff --git a/gcc/config/arm/unspecs.md b/gcc/config/arm/unspecs.md
index 8f9dbcb..1941673 100644
--- a/gcc/config/arm/unspecs.md
+++ b/gcc/config/arm/unspecs.md
@@ -86,9 +86,6 @@
   UNSPEC_PROBE_STACK    ; Probe stack memory reference
   UNSPEC_NONSECURE_MEM	; Represent non-secure memory in ARMv8-M with
 			; security extension
-  UNSPEC_SP_SET		; Represent the setting of stack protector's canary
-  UNSPEC_SP_TEST	; Represent the testing of stack protector's canary
-			; against the guard.
 ])
 
 (define_c_enum "unspec" [