diff options
Diffstat (limited to 'gcc/config/arm/arm.c')
| -rw-r--r-- | gcc/config/arm/arm.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index 701ab4c..00ccb92 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. */ |