re PR target/9703 ([arm] Accessing data through constant pool more times could be solved in less instructions)

	* cselib.c (cselib_init): Change RTX_SIZE to RTX_CODE_SIZE.
	* emit-rtl.c (copy_rtx_if_shared_1): Use shallow_copy_rtx.
	(copy_insn_1): Likewise.  Don't copy each field individually.
	Reindent.
	* read-rtl.c (apply_macro_to_rtx): Use RTX_CODE_SIZE instead
	of RTX_SIZE.
	* reload1.c (eliminate_regs): Use shallow_copy_rtx.
	* rtl.c (rtx_size): Rename variable to...
	(rtx_code_size): ...this.
	(rtx_size): New function.
	(rtx_alloc_stat): Use RTX_CODE_SIZE instead of RTX_SIZE.
	(copy_rtx): Use shallow_copy_rtx.  Don't copy each field individually.
	Reindent.
	(shallow_copy_rtx_stat): Use rtx_size instead of RTX_SIZE.
	* rtl.h (rtx_code_size): New variable.
	(rtx_size): Change from a variable to a function.
	(RTX_SIZE): Rename to...
	(RTX_CODE_SIZE): ...this.

	PR target/9703
	PR tree-optimization/17106
	* doc/tm.texi (TARGET_USE_BLOCKS_FOR_CONSTANT_P): Document.
	(Anchored Addresses): New section.
	* doc/invoke.texi (-fsection-anchors): Document.
	* doc/rtl.texi (SYMBOL_REF_IN_BLOCK_P, SYMBOL_FLAG_IN_BLOCK): Likewise.
	(SYMBOL_REF_ANCHOR_P, SYMBOL_FLAG_ANCHOR): Likewise.
	(SYMBOL_REF_BLOCK, SYMBOL_REF_BLOCK_OFFSET): Likewise.
	* hooks.c (hook_bool_mode_rtx_false): New function.
	* hooks.h (hook_bool_mode_rtx_false): Declare.
	* gengtype.c (create_optional_field): New function.
	(adjust_field_rtx_def): Add the "block_sym" field for SYMBOL_REFs when
	SYMBOL_REF_IN_BLOCK_P is true.
	* target.h (output_anchor, use_blocks_for_constant_p): New hooks.
	(min_anchor_offset, max_anchor_offset): Likewise.
	(use_anchors_for_symbol_p): New hook.
	* toplev.c (compile_file): Call output_object_blocks.
	(target_supports_section_anchors_p): New function.
	(process_options): Check that -fsection-anchors is only used on
	targets that support it and when -funit-at-a-time is in effect.
	* tree-ssa-loop-ivopts.c (prepare_decl_rtl): Only create DECL_RTL
	if the decl doesn't have one.
	* dwarf2out.c: Remove instantiations of VEC(rtx,gc).
	* expr.c (emit_move_multi_word, emit_move_insn): Pass the result
	of force_const_mem through use_anchored_address.
	(expand_expr_constant): New function.
	(expand_expr_addr_expr_1): Call it.  Use the same modifier when
	calling expand_expr for INDIRECT_REF.
	(expand_expr_real_1): Pass DECL_RTL through use_anchored_address
	for all modifiers except EXPAND_INITIALIZER.  Use expand_expr_constant.
	* expr.h (use_anchored_address): Declare.
	* loop-unroll.c: Don't declare rtx vectors here.
	* explow.c: Include output.h.
	(validize_mem): Call use_anchored_address.
	(use_anchored_address): New function.
	* common.opt (-fsection-anchors): New switch.
	* varasm.c (object_block_htab, anchor_labelno): New variables.
	(hash_section, object_block_entry_eq, object_block_entry_hash)
	(use_object_blocks_p, get_block_for_section, create_block_symbol)
	(use_blocks_for_decl_p, change_symbol_section): New functions.
	(get_variable_section): New function, split out from assemble_variable.
	(make_decl_rtl): Create a block symbol if use_object_blocks_p and
	use_blocks_for_decl_p say so.  Use change_symbol_section if the
	symbol has already been created.
	(assemble_variable_contents): New function, split out from...
	(assemble_variable): ...here.  Don't output any code for
	block symbols; just pass them to place_block_symbol.
	Use get_variable_section and assemble_variable_contents.
	(get_constant_alignment, get_constant_section, get_constant_size): New
	functions, split from output_constant_def_contents.
	(build_constant_desc): Create a block symbol if use_object_blocks_p
	says so.  Or into SYMBOL_REF_FLAGS.
	(assemble_constant_contents): New function, split from...
	(output_constant_def_contents): ...here.  Don't output any code
	for block symbols; just pass them to place_section_symbol.
	Use get_constant_section and get_constant_alignment.
	(force_const_mem): Create a block symbol if use_object_blocks_p and
	use_blocks_for_constant_p say so.  Or into SYMBOL_REF_FLAGS.
	(output_constant_pool_1): Add an explicit alignment argument.
	Don't switch sections here.
	(output_constant_pool): Adjust call to output_constant_pool_1.
	Switch sections here instead.  Don't output anything for block symbols;
	just pass them to place_block_symbol.
	(init_varasm_once): Initialize object_block_htab.
	(default_encode_section_info): Keep the old SYMBOL_FLAG_IN_BLOCK.
	(default_asm_output_anchor, default_use_aenchors_for_symbol_p)
	(place_block_symbol, get_section_anchor, output_object_block)
	(output_object_block_htab, output_object_blocks): New functions.
	* target-def.h (TARGET_ASM_OUTPUT_ANCHOR): New macro.
	(TARGET_ASM_OUT): Include it.
	(TARGET_USE_BLOCKS_FOR_CONSTANT_P): New macro.
	(TARGET_MIN_ANCHOR_OFFSET, TARGET_MAX_ANCHOR_OFFSET): New macros.
	(TARGET_USE_ANCHORS_FOR_SYMBOL_P): New macro.
	(TARGET_INITIALIZER): Include them.
	* rtl.c (rtl_check_failed_block_symbol): New function.
	* rtl.h: Include vec.h.  Declare heap and gc rtx vectors.
	(block_symbol, object_block): New structures.
	(rtx_def): Add a block_symbol field to the union.
	(BLOCK_SYMBOL_CHECK): New macro.
	(rtl_check_failed_block_symbol): Declare.
	(SYMBOL_FLAG_IN_BLOCK, SYMBOL_FLAG_ANCHOR): New SYMBOL_REF flags.
	(SYMBOL_REF_IN_BLOCK_P, SYMBOL_REF_ANCHOR_P): New predicates.
	(SYMBOL_FLAG_MACH_DEP_SHIFT): Bump by 2.
	(SYMBOL_REF_BLOCK, SYMBOL_REF_BLOCK_OFFSET): New accessors.
	* output.h (output_section_symbols): Declare.
	(object_block): Name structure.
	(place_section_symbol, get_section_anchor, default_asm_output_anchor)
	(default_use_anchors_for_symbol_p): Declare.
	* Makefile.in (RTL_BASE_H): Add vec.h.
	(explow.o): Depend on output.h.
	* config/rs6000/rs6000.c (TARGET_MIN_ANCHOR_OFFSET): Override default.
	(TARGET_MAX_ANCHOR_OFFSET): Likewise.
	(TARGET_USE_BLOCKS_FOR_CONSTANT_P): Likewise.
	(rs6000_use_blocks_for_constant_p): New function.

From-SVN: r111254

1 files changed, 40 insertions, 26 deletions

diff --git a/gcc/expr.c b/gcc/expr.c
index 92d8d28..0107f2a 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -3081,7 +3081,7 @@ emit_move_multi_word (enum machine_mode mode, rtx x, rtx y)
 	 be able to get a part of Y.  */
       if (ypart == 0 && CONSTANT_P (y))
 	{
-	  y = force_const_mem (mode, y);
+	  y = use_anchored_address (force_const_mem (mode, y));
 	  ypart = operand_subword (y, i, 1, mode);
 	}
       else if (ypart == 0)
@@ -3194,6 +3194,8 @@ emit_move_insn (rtx x, rtx y)
 	     of the non-legitimate constant.  */
 	  if (!y)
 	    y = y_cst;
+	  else
+	    y = use_anchored_address (y);
 	}
     }
 
@@ -6280,6 +6282,20 @@ expand_operands (tree exp0, tree exp1, rtx target, rtx *op0, rtx *op1,
 }
 
 
+/* Return a MEM that constains constant EXP.  DEFER is as for
+   output_constant_def and MODIFIER is as for expand_expr.  */
+
+static rtx
+expand_expr_constant (tree exp, int defer, enum expand_modifier modifier)
+{
+  rtx mem;
+
+  mem = output_constant_def (exp, defer);
+  if (modifier != EXPAND_INITIALIZER)
+    mem = use_anchored_address (mem);
+  return mem;
+}
+
 /* A subroutine of expand_expr_addr_expr.  Evaluate the address of EXP.
    The TARGET, TMODE and MODIFIER arguments are as for expand_expr.  */
 
@@ -6301,14 +6317,14 @@ expand_expr_addr_expr_1 (tree exp, rtx target, enum machine_mode tmode,
      exception here is STRING_CST.  */
   if (TREE_CODE (exp) == CONSTRUCTOR
       || CONSTANT_CLASS_P (exp))
-    return XEXP (output_constant_def (exp, 0), 0);
+    return XEXP (expand_expr_constant (exp, 0, modifier), 0);
 
   /* Everything must be something allowed by is_gimple_addressable.  */
   switch (TREE_CODE (exp))
     {
     case INDIRECT_REF:
       /* This case will happen via recursion for &a->b.  */
-      return expand_expr (TREE_OPERAND (exp, 0), target, tmode, EXPAND_NORMAL);
+      return expand_expr (TREE_OPERAND (exp, 0), target, tmode, modifier);
 
     case CONST_DECL:
       /* Recurse and make the output_constant_def clause above handle this.  */
@@ -6579,7 +6595,7 @@ static rtx
 expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 		    enum expand_modifier modifier, rtx *alt_rtl)
 {
-  rtx op0, op1, temp;
+  rtx op0, op1, temp, decl_rtl;
   tree type = TREE_TYPE (exp);
   int unsignedp;
   enum machine_mode mode;
@@ -6701,7 +6717,8 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 
     case FUNCTION_DECL:
     case RESULT_DECL:
-      gcc_assert (DECL_RTL (exp));
+      decl_rtl = DECL_RTL (exp);
+      gcc_assert (decl_rtl);
 
       /* Ensure variable marked as used even if it doesn't go through
 	 a parser.  If it hasn't be used yet, write out an external
@@ -6728,27 +6745,24 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 	 from its initializer, while the initializer is still being parsed.
 	 See expand_decl.  */
 
-      if (MEM_P (DECL_RTL (exp))
-	       && REG_P (XEXP (DECL_RTL (exp), 0)))
-	temp = validize_mem (DECL_RTL (exp));
+      if (MEM_P (decl_rtl) && REG_P (XEXP (decl_rtl, 0)))
+	temp = validize_mem (decl_rtl);
 
       /* If DECL_RTL is memory, we are in the normal case and either
 	 the address is not valid or it is not a register and -fforce-addr
 	 is specified, get the address into a register.  */
 
-      else if (MEM_P (DECL_RTL (exp))
-	       && modifier != EXPAND_CONST_ADDRESS
-	       && modifier != EXPAND_SUM
-	       && modifier != EXPAND_INITIALIZER
-	       && (! memory_address_p (DECL_MODE (exp),
-				       XEXP (DECL_RTL (exp), 0))
-		   || (flag_force_addr
-		       && !REG_P (XEXP (DECL_RTL (exp), 0)))))
+      else if (MEM_P (decl_rtl) && modifier != EXPAND_INITIALIZER)
 	{
 	  if (alt_rtl)
-	    *alt_rtl = DECL_RTL (exp);
-	  temp = replace_equiv_address (DECL_RTL (exp),
-					copy_rtx (XEXP (DECL_RTL (exp), 0)));
+	    *alt_rtl = decl_rtl;
+	  decl_rtl = use_anchored_address (decl_rtl);
+	  if (modifier != EXPAND_CONST_ADDRESS
+	      && modifier != EXPAND_SUM
+	      && (!memory_address_p (DECL_MODE (exp), XEXP (decl_rtl, 0))
+		  || (flag_force_addr && !REG_P (XEXP (decl_rtl, 0)))))
+	    temp = replace_equiv_address (decl_rtl,
+					  copy_rtx (XEXP (decl_rtl, 0)));
 	}
 
       /* If we got something, return it.  But first, set the alignment
@@ -6765,8 +6779,8 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 	 must be a promoted value.  We return a SUBREG of the wanted mode,
 	 but mark it so that we know that it was already extended.  */
 
-      if (REG_P (DECL_RTL (exp))
-	  && GET_MODE (DECL_RTL (exp)) != DECL_MODE (exp))
+      if (REG_P (decl_rtl)
+	  && GET_MODE (decl_rtl) != DECL_MODE (exp))
 	{
 	  enum machine_mode pmode;
 	  
@@ -6775,15 +6789,15 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 	  pmode = promote_mode (type, DECL_MODE (exp), &unsignedp,
 				(TREE_CODE (exp) == RESULT_DECL
 				 || TREE_CODE (exp) == PARM_DECL) ? 1 : 0);
-	  gcc_assert (GET_MODE (DECL_RTL (exp)) == pmode);
+	  gcc_assert (GET_MODE (decl_rtl) == pmode);
 
-	  temp = gen_lowpart_SUBREG (mode, DECL_RTL (exp));
+	  temp = gen_lowpart_SUBREG (mode, decl_rtl);
 	  SUBREG_PROMOTED_VAR_P (temp) = 1;
 	  SUBREG_PROMOTED_UNSIGNED_SET (temp, unsignedp);
 	  return temp;
 	}
 
-      return DECL_RTL (exp);
+      return decl_rtl;
 
     case INTEGER_CST:
       temp = immed_double_const (TREE_INT_CST_LOW (exp),
@@ -6852,7 +6866,7 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
       /* ... fall through ...  */
 
     case STRING_CST:
-      temp = output_constant_def (exp, 1);
+      temp = expand_expr_constant (exp, 1, modifier);
 
       /* temp contains a constant address.
 	 On RISC machines where a constant address isn't valid,
@@ -6953,7 +6967,7 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 		    || modifier == EXPAND_CONST_ADDRESS)
 		   && TREE_CONSTANT (exp)))
 	{
-	  rtx constructor = output_constant_def (exp, 1);
+	  rtx constructor = expand_expr_constant (exp, 1, modifier);
 
 	  if (modifier != EXPAND_CONST_ADDRESS
 	      && modifier != EXPAND_INITIALIZER