From 956db28eb5782cc4f86f146d9250ca5f0f16e3ce Mon Sep 17 00:00:00 2001 From: Kyrylo Tkachov Date: Wed, 9 Sep 2015 08:41:41 +0000 Subject: [PATCH] [ARM][3/3] Expand mod by power of 2 * config/arm/arm.md (*subsi3_compare0): Rename to... (subsi3_compare0): ... This. (modsi3): New define_expand. * config/arm/arm.c (arm_new_rtx_costs, MOD case): Handle case when operand is power of 2. * gcc.target/aarch64/mod_2.x: New file. * gcc.target/aarch64/mod_256.x: Likewise. * gcc.target/arm/mod_2.c: New test. * gcc.target/arm/mod_256.c: Likewise. * gcc.target/aarch64/mod_2.c: Likewise. * gcc.target/aarch64/mod_256.c: Likewise. From-SVN: r227586 --- gcc/ChangeLog | 8 +++ gcc/config/arm/arm.c | 18 ++++++ gcc/config/arm/arm.md | 71 +++++++++++++++++++++- gcc/testsuite/ChangeLog | 9 +++ gcc/testsuite/gcc.target/aarch64/mod_2.c | 7 +++ gcc/testsuite/gcc.target/aarch64/mod_2.x | 5 ++ gcc/testsuite/gcc.target/aarch64/mod_256.c | 6 ++ gcc/testsuite/gcc.target/aarch64/mod_256.x | 5 ++ gcc/testsuite/gcc.target/arm/mod_2.c | 8 +++ gcc/testsuite/gcc.target/arm/mod_256.c | 8 +++ 10 files changed, 144 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.target/aarch64/mod_2.c create mode 100644 gcc/testsuite/gcc.target/aarch64/mod_2.x create mode 100644 gcc/testsuite/gcc.target/aarch64/mod_256.c create mode 100644 gcc/testsuite/gcc.target/aarch64/mod_256.x create mode 100644 gcc/testsuite/gcc.target/arm/mod_2.c create mode 100644 gcc/testsuite/gcc.target/arm/mod_256.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 25ecf5a89a5..618bbe63abc 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2015-09-09 Kyrylo Tkachov + + * config/arm/arm.md (*subsi3_compare0): Rename to... + (subsi3_compare0): ... This. + (modsi3): New define_expand. + * config/arm/arm.c (arm_new_rtx_costs, MOD case): Handle case + when operand is power of 2. + 2015-09-09 Kyrylo Tkachov * config/aarch64/aarch64.md (mod3): New define_expand. diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index f343d533396..5f3180d38ce 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -9580,6 +9580,24 @@ arm_new_rtx_costs (rtx x, enum rtx_code code, enum rtx_code outer_code, return false; /* All arguments must be in registers. */ case MOD: + /* MOD by a power of 2 can be expanded as: + rsbs r1, r0, #0 + and r0, r0, #(n - 1) + and r1, r1, #(n - 1) + rsbpl r0, r1, #0. */ + if (CONST_INT_P (XEXP (x, 1)) + && exact_log2 (INTVAL (XEXP (x, 1))) > 0 + && mode == SImode) + { + *cost += COSTS_N_INSNS (3); + + if (speed_p) + *cost += 2 * extra_cost->alu.logical + + extra_cost->alu.arith; + return true; + } + + /* Fall-through. */ case UMOD: *cost = LIBCALL_COST (2); return false; /* All arguments must be in registers. */ diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md index b6c20478f9c..775ca25d816 100644 --- a/gcc/config/arm/arm.md +++ b/gcc/config/arm/arm.md @@ -1229,7 +1229,7 @@ "" ) -(define_insn "*subsi3_compare0" +(define_insn "subsi3_compare0" [(set (reg:CC_NOOV CC_REGNUM) (compare:CC_NOOV (minus:SI (match_operand:SI 1 "arm_rhs_operand" "r,r,I") @@ -11142,6 +11142,75 @@ "" ) +;; ARM-specific expansion of signed mod by power of 2 +;; using conditional negate. +;; For r0 % n where n is a power of 2 produce: +;; rsbs r1, r0, #0 +;; and r0, r0, #(n - 1) +;; and r1, r1, #(n - 1) +;; rsbpl r0, r1, #0 + +(define_expand "modsi3" + [(match_operand:SI 0 "register_operand" "") + (match_operand:SI 1 "register_operand" "") + (match_operand:SI 2 "const_int_operand" "")] + "TARGET_32BIT" + { + HOST_WIDE_INT val = INTVAL (operands[2]); + + if (val <= 0 + || exact_log2 (val) <= 0) + FAIL; + + rtx mask = GEN_INT (val - 1); + + /* In the special case of x0 % 2 we can do the even shorter: + cmp r0, #0 + and r0, r0, #1 + rsblt r0, r0, #0. */ + + if (val == 2) + { + rtx cc_reg = arm_gen_compare_reg (LT, + operands[1], const0_rtx, NULL_RTX); + rtx cond = gen_rtx_LT (SImode, cc_reg, const0_rtx); + rtx masked = gen_reg_rtx (SImode); + + emit_insn (gen_andsi3 (masked, operands[1], mask)); + emit_move_insn (operands[0], + gen_rtx_IF_THEN_ELSE (SImode, cond, + gen_rtx_NEG (SImode, + masked), + masked)); + DONE; + } + + rtx neg_op = gen_reg_rtx (SImode); + rtx_insn *insn = emit_insn (gen_subsi3_compare0 (neg_op, const0_rtx, + operands[1])); + + /* Extract the condition register and mode. */ + rtx cmp = XVECEXP (PATTERN (insn), 0, 0); + rtx cc_reg = SET_DEST (cmp); + rtx cond = gen_rtx_GE (SImode, cc_reg, const0_rtx); + + emit_insn (gen_andsi3 (operands[0], operands[1], mask)); + + rtx masked_neg = gen_reg_rtx (SImode); + emit_insn (gen_andsi3 (masked_neg, neg_op, mask)); + + /* We want a conditional negate here, but emitting COND_EXEC rtxes + during expand does not always work. Do an IF_THEN_ELSE instead. */ + emit_move_insn (operands[0], + gen_rtx_IF_THEN_ELSE (SImode, cond, + gen_rtx_NEG (SImode, masked_neg), + operands[0])); + + + DONE; + } +) + (define_expand "bswapsi2" [(set (match_operand:SI 0 "s_register_operand" "=r") (bswap:SI (match_operand:SI 1 "s_register_operand" "r")))] diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 3506d4a3a40..360fe70b8d0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2015-09-09 Kyrylo Tkachov + + * gcc.target/aarch64/mod_2.x: New file. + * gcc.target/aarch64/mod_256.x: Likewise. + * gcc.target/arm/mod_2.c: New test. + * gcc.target/arm/mod_256.c: Likewise. + * gcc.target/aarch64/mod_2.c: Likewise. + * gcc.target/aarch64/mod_256.c: Likewise. + 2015-09-09 Jakub Jelinek PR c++/67504 diff --git a/gcc/testsuite/gcc.target/aarch64/mod_2.c b/gcc/testsuite/gcc.target/aarch64/mod_2.c new file mode 100644 index 00000000000..2645c18e741 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/mod_2.c @@ -0,0 +1,7 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mcpu=cortex-a57 -save-temps" } */ + +#include "mod_2.x" + +/* { dg-final { scan-assembler "csneg\t\[wx\]\[0-9\]*" } } */ +/* { dg-final { scan-assembler-times "and\t\[wx\]\[0-9\]*" 1 } } */ diff --git a/gcc/testsuite/gcc.target/aarch64/mod_2.x b/gcc/testsuite/gcc.target/aarch64/mod_2.x new file mode 100644 index 00000000000..2b079a4b883 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/mod_2.x @@ -0,0 +1,5 @@ +int +f (int x) +{ + return x % 2; +} diff --git a/gcc/testsuite/gcc.target/aarch64/mod_256.c b/gcc/testsuite/gcc.target/aarch64/mod_256.c new file mode 100644 index 00000000000..567332c04e1 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/mod_256.c @@ -0,0 +1,6 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -mcpu=cortex-a57 -save-temps" } */ + +#include "mod_256.x" + +/* { dg-final { scan-assembler "csneg\t\[wx\]\[0-9\]*" } } */ diff --git a/gcc/testsuite/gcc.target/aarch64/mod_256.x b/gcc/testsuite/gcc.target/aarch64/mod_256.x new file mode 100644 index 00000000000..c1de42ce389 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/mod_256.x @@ -0,0 +1,5 @@ +int +f (int x) +{ + return x % 256; +} diff --git a/gcc/testsuite/gcc.target/arm/mod_2.c b/gcc/testsuite/gcc.target/arm/mod_2.c new file mode 100644 index 00000000000..93017a10683 --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/mod_2.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target arm32 } */ +/* { dg-options "-O2 -mcpu=cortex-a57 -save-temps" } */ + +#include "../aarch64/mod_2.x" + +/* { dg-final { scan-assembler "rsblt\tr\[0-9\]*" } } */ +/* { dg-final { scan-assembler-times "and\tr\[0-9\].*1" 1 } } */ diff --git a/gcc/testsuite/gcc.target/arm/mod_256.c b/gcc/testsuite/gcc.target/arm/mod_256.c new file mode 100644 index 00000000000..ccb7f3cf68d --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/mod_256.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target arm32 } */ +/* { dg-options "-O2 -mcpu=cortex-a57 -save-temps" } */ + +#include "../aarch64/mod_256.x" + +/* { dg-final { scan-assembler "rsbpl\tr\[0-9\]*" } } */ + -- 2.30.2