This patch replaces three separate default definitions of SLOW_UNALIGNED_ACCESS with a single global one. Note that tm.texi requires SLOW_UNALIGNED_ACCESS to be true if STRICT_ALIGNMENT.
Tested on x86_64-linux-gnu, powerpc64-linux-gnu and mipsisa64-elf. Applied as obvious. Richard gcc/ * defaults.h (SLOW_UNALIGNED_ACCESS): Provide default definition. * expmed.c (SLOW_UNALIGNED_ACCESS): Remove default definition. * expr.c (SLOW_UNALIGNED_ACCESS): Likewise. * lra-constraints.c (SLOW_UNALIGNED_ACCESS): Likewise. (simplify_operand_subreg): Don't check STRICT_ALIGNMENT here. Index: gcc/defaults.h =================================================================== --- gcc/defaults.h 2012-08-02 21:10:06.000000000 +0100 +++ gcc/defaults.h 2012-10-28 10:30:47.340353996 +0000 @@ -1218,6 +1218,10 @@ #define MINIMUM_ALIGNMENT(EXP,MODE,ALIGN #define ATTRIBUTE_ALIGNED_VALUE BIGGEST_ALIGNMENT #endif +#ifndef SLOW_UNALIGNED_ACCESS +#define SLOW_UNALIGNED_ACCESS(MODE, ALIGN) STRICT_ALIGNMENT +#endif + /* For most ports anything that evaluates to a constant symbolic or integer value is acceptable as a constant address. */ #ifndef CONSTANT_ADDRESS_P Index: gcc/expmed.c =================================================================== --- gcc/expmed.c 2012-10-28 10:25:12.000000000 +0000 +++ gcc/expmed.c 2012-10-28 10:30:44.178354004 +0000 @@ -69,11 +69,6 @@ static rtx expand_sdiv_pow2 (enum machin /* Test whether a value is zero of a power of two. */ #define EXACT_POWER_OF_2_OR_ZERO_P(x) (((x) & ((x) - 1)) == 0) -#ifndef SLOW_UNALIGNED_ACCESS -#define SLOW_UNALIGNED_ACCESS(MODE, ALIGN) STRICT_ALIGNMENT -#endif - - /* Reduce conditional compilation elsewhere. */ #ifndef HAVE_insv #define HAVE_insv 0 Index: gcc/expr.c =================================================================== --- gcc/expr.c 2012-10-25 10:08:06.000000000 +0100 +++ gcc/expr.c 2012-10-28 10:31:44.133353857 +0000 @@ -189,12 +189,6 @@ #define STORE_BY_PIECES_P(SIZE, ALIGN) \ (move_by_pieces_ninsns (SIZE, ALIGN, STORE_MAX_PIECES + 1) \ < (unsigned int) MOVE_RATIO (optimize_insn_for_speed_p ())) #endif - -/* SLOW_UNALIGNED_ACCESS is nonzero if unaligned accesses are very slow. */ - -#ifndef SLOW_UNALIGNED_ACCESS -#define SLOW_UNALIGNED_ACCESS(MODE, ALIGN) STRICT_ALIGNMENT -#endif /* This is run to set up which modes can be used directly in memory and to initialize the block move optab. It is run Index: gcc/lra-constraints.c =================================================================== --- gcc/lra-constraints.c 2012-10-26 11:50:16.000000000 +0100 +++ gcc/lra-constraints.c 2012-10-28 10:32:02.499353813 +0000 @@ -1105,10 +1105,6 @@ process_addr_reg (rtx *loc, rtx *before, return true; } -#ifndef SLOW_UNALIGNED_ACCESS -#define SLOW_UNALIGNED_ACCESS(mode, align) 0 -#endif - /* Make reloads for subreg in operand NOP with internal subreg mode REG_MODE, add new reloads for further processing. Return true if any reload was generated. */ @@ -1132,8 +1128,7 @@ simplify_operand_subreg (int nop, enum m address might violate the necessary alignment or the access might be slow. So take this into consideration. */ if ((MEM_P (reg) - && ((! STRICT_ALIGNMENT - && ! SLOW_UNALIGNED_ACCESS (mode, MEM_ALIGN (reg))) + && (! SLOW_UNALIGNED_ACCESS (mode, MEM_ALIGN (reg)) || MEM_ALIGN (reg) >= GET_MODE_ALIGNMENT (mode))) || (REG_P (reg) && REGNO (reg) < FIRST_PSEUDO_REGISTER)) {