Turn CONSTANT_ALIGNMENT into a hook

The definition:

  #define CONSTANT_ALIGNMENT(EXP, ALIGN) \
    (TREE_CODE (EXP) == STRING_CST \
     && (ALIGN) < BITS_PER_WORD ? BITS_PER_WORD : (ALIGN))

was very common, so the patch adds a canned definition for that,
called constant_alignment_word_strings.  Some ports had a variation
that used a port-local FASTEST_ALIGNMENT instead of BITS_PER_WORD;
the patch uses constant_alignment_word_strings if FASTEST_ALIGNMENT
was always BITS_PER_WORD and a port-local hook function otherwise.

2017-09-25  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* target.def (constant_alignment): New hook.
	* defaults.h (CONSTANT_ALIGNMENT): Delete.
	* doc/tm.texi.in (CONSTANT_ALIGNMENT): Replace with...
	(TARGET_CONSTANT_ALIGNMENT): ...this new hook.
	* doc/tm.texi: Regenerate.
	* targhooks.h (default_constant_alignment): Declare.
	(constant_alignment_word_strings): Likewise.
	* targhooks.c (default_constant_alignment): New function.
	(constant_alignment_word_strings): Likewise.
	* builtins.c (get_object_alignment_2): Use targetm.constant_alignment
	instead of CONSTANT_ALIGNMENT.
	* varasm.c (align_variable, get_variable_align, build_constant_desc)
	(force_const_mem): Likewise.
	* config/aarch64/aarch64.h (CONSTANT_ALIGNMENT): Delete.
	* config/aarch64/aarch64.c (aarch64_constant_alignment): New function.
	(aarch64_classify_address): Call it instead of CONSTANT_ALIGNMENT.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/alpha/alpha.h (CONSTANT_ALIGNMENT): Delete commented-out
	definition.
	* config/arc/arc.h (CONSTANT_ALIGNMENT): Delete.
	* config/arc/arc.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/arm/arm.h (CONSTANT_ALIGNMENT_FACTOR): Delete.
	(CONSTANT_ALIGNMENT): Likewise.
	* config/arm/arm.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(arm_constant_alignment): New function.
	* config/bfin/bfin.h (CONSTANT_ALIGNMENT): Delete.
	* config/bfin/bfin.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/cr16/cr16.h (CONSTANT_ALIGNMENT): Delete.
	* config/cr16/cr16.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/cris/cris.h (CONSTANT_ALIGNMENT): Delete.
	* config/cris/cris.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(cris_constant_alignment): New function.
	* config/epiphany/epiphany.h (CONSTANT_ALIGNMENT): Delete.
	* config/epiphany/epiphany.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(epiphany_constant_alignment): New function.
	* config/fr30/fr30.h (CONSTANT_ALIGNMENT): Delete.
	* config/fr30/fr30.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/frv/frv.h (CONSTANT_ALIGNMENT): Delete.
	* config/frv/frv.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/ft32/ft32.h (CONSTANT_ALIGNMENT): Delete.
	* config/ft32/ft32.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/i386/i386.h (CONSTANT_ALIGNMENT): Delete.
	* config/i386/i386-protos.h (ix86_constant_alignment): Delete.
	* config/i386/i386.c (ix86_constant_alignment): Make static.
	Use the same interface as the target hook.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/ia64/ia64.h (CONSTANT_ALIGNMENT): Delete.
	* config/ia64/ia64.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/iq2000/iq2000.h (CONSTANT_ALIGNMENT): Delete.
	* config/iq2000/iq2000.c (iq2000_constant_alignment): New function.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/lm32/lm32.h (CONSTANT_ALIGNMENT): Delete.
	* config/lm32/lm32.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/m32r/m32r.h (CONSTANT_ALIGNMENT): Delete.
	* config/m32r/m32r.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/mcore/mcore.h (CONSTANT_ALIGNMENT): Delete.
	* config/mcore/mcore.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/microblaze/microblaze.h (CONSTANT_ALIGNMENT): Delete.
	* config/microblaze/microblaze.c (microblaze_constant_alignment):
	New function.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/mips/mips.h (CONSTANT_ALIGNMENT): Delete.
	* config/mips/mips.c (mips_constant_alignment): New function.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/mmix/mmix.h (CONSTANT_ALIGNMENT): Delete.
	* config/mmix/mmix-protos.h (mmix_constant_alignment): Delete.
	* config/mmix/mmix.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(mmix_constant_alignment): Make static.  Use the same interface
	as the target hook.
	* config/moxie/moxie.h (CONSTANT_ALIGNMENT): Delete.
	* config/moxie/moxie.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/nios2/nios2.h (CONSTANT_ALIGNMENT): Delete.
	* config/nios2/nios2.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/pa/pa.h (CONSTANT_ALIGNMENT): Delete.
	* config/pa/pa.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/powerpcspe/powerpcspe.h (CONSTANT_ALIGNMENT): Delete.
	* config/powerpcspe/powerpcspe.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(rs6000_constant_alignment): New function.
	* config/riscv/riscv.h (CONSTANT_ALIGNMENT): Delete.
	* config/riscv/riscv.c (riscv_constant_alignment): New function.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/rs6000/rs6000.h (CONSTANT_ALIGNMENT): Delete.
	* config/rs6000/rs6000.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(rs6000_constant_alignment): New function.
	* config/s390/s390.h (CONSTANT_ALIGNMENT): Delete.
	* config/s390/s390.c (s390_constant_alignment): New function.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/sh/sh.h (CONSTANT_ALIGNMENT): Delete.
	* config/sh/sh.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/sparc/sparc.h (CONSTANT_ALIGNMENT): Delete.
	* config/sparc/sparc.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(sparc_constant_alignment): New function.
	* config/spu/spu.h (CONSTANT_ALIGNMENT): Delete.
	* config/spu/spu.c (spu_constant_alignment): New function.
	(TARGET_CONSTANT_ALIGNMENT): Redefine.
	* config/stormy16/stormy16.h (CONSTANT_ALIGNMENT): Delete.
	* config/stormy16/stormy16.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/tilegx/tilegx.h (CONSTANT_ALIGNMENT): Delete.
	* config/tilegx/tilegx.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/tilepro/tilepro.h (CONSTANT_ALIGNMENT): Delete.
	* config/tilepro/tilepro.c (TARGET_CONSTANT_ALIGNMENT): Redefine to
	constant_alignment_word_strings.
	* config/visium/visium.h (CONSTANT_ALIGNMENT): Delete.
	* config/visium/visium.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(visium_constant_alignment): New function.
	* config/xtensa/xtensa.h (CONSTANT_ALIGNMENT): Delete.
	* config/xtensa/xtensa.c (TARGET_CONSTANT_ALIGNMENT): Redefine.
	(xtensa_constant_alignment): New function.
	* system.h (CONSTANT_ALIGNMENT): Poison.

From-SVN: r253154

1 files changed, 7 insertions, 9 deletions

diff --git a/gcc/varasm.c b/gcc/varasm.c
index 1c66c26..55fca76 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -1055,7 +1055,7 @@ align_variable (tree decl, bool dont_output_data)
 	      && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
 	    {
 	      unsigned int const_align
-		= CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
+		= targetm.constant_alignment (DECL_INITIAL (decl), align);
 	      /* Don't increase alignment too much for TLS variables - TLS
 		 space is too precious.  */
 	      if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
@@ -1106,8 +1106,8 @@ get_variable_align (tree decl)
 	     to mark offlined constructors.  */
 	  && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
 	{
-	  unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
-							 align);
+	  unsigned int const_align
+	    = targetm.constant_alignment (DECL_INITIAL (decl), align);
 	  /* Don't increase alignment too much for TLS variables - TLS space
 	     is too precious.  */
 	  if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
@@ -3326,12 +3326,10 @@ build_constant_desc (tree exp)
      Instead we set the flag that will be recognized in make_decl_rtl.  */
   DECL_IN_CONSTANT_POOL (decl) = 1;
   DECL_INITIAL (decl) = desc->value;
-  /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
-     architectures so use DATA_ALIGNMENT as well, except for strings.  */
+  /* ??? targetm.constant_alignment hasn't been updated for vector types on
+     most architectures so use DATA_ALIGNMENT as well, except for strings.  */
   if (TREE_CODE (exp) == STRING_CST)
-    {
-      SET_DECL_ALIGN (decl, CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl)));
-    }
+    SET_DECL_ALIGN (decl, targetm.constant_alignment (exp, DECL_ALIGN (decl)));
   else
     align_variable (decl, 0);
 
@@ -3790,7 +3788,7 @@ force_const_mem (machine_mode mode, rtx x)
 
   tree type = lang_hooks.types.type_for_mode (mode, 0);
   if (type != NULL_TREE)
-    align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
+    align = targetm.constant_alignment (make_tree (type, x), align);
 
   pool->offset += (align / BITS_PER_UNIT) - 1;
   pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);