From: Richard Earnshaw Date: Thu, 2 Aug 2012 16:20:22 +0000 (+0000) Subject: arm.c (arm_gen_constant): Use UBFX for some AND operations when available. X-Git-Tag: releases/gcc-4.8.0~4159 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ca26f665dd7204fa930dc7f6a936ac526cd66f74;p=thirdparty%2Fgcc.git arm.c (arm_gen_constant): Use UBFX for some AND operations when available. * arm.c (arm_gen_constant): Use UBFX for some AND operations when available. From-SVN: r190088 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 973ae0d35871..578b0a054854 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2012-08-02 Richard Earnshaw + + * arm.c (arm_gen_constant): Use UBFX for some AND operations when + available. + 2012-08-02 Richard Guenther * tree-into-ssa.c (struct common_info_d): New struct. diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index 701ab4cfe2d9..00ccb9280de7 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -2982,6 +2982,31 @@ arm_gen_constant (enum rtx_code code, enum machine_mode mode, rtx cond, return 1; } + /* On targets with UXTH/UBFX, we can deal with AND (2^N)-1 in a single + insn. */ + if (code == AND && (i = exact_log2 (remainder + 1)) > 0 + && (arm_arch_thumb2 || (i == 16 && arm_arch6 && mode == SImode))) + { + if (generate) + { + if (mode == SImode && i == 16) + /* Use UXTH in preference to UBFX, since on Thumb2 it's a + smaller insn. */ + emit_constant_insn (cond, + gen_zero_extendhisi2 + (target, gen_lowpart (HImode, source))); + else + /* Extz only supports SImode, but we can coerce the operands + into that mode. */ + emit_constant_insn (cond, + gen_extzv_t2 (gen_lowpart (mode, target), + gen_lowpart (mode, source), + GEN_INT (i), const0_rtx)); + } + + return 1; + } + /* Calculate a few attributes that may be useful for specific optimizations. */ /* Count number of leading zeros. */