This patch adds separate params for rtl unroller so that they can be
tunned accordingly. Default values I have are based on some testing on
aarch64. I am happy to leave it as the current value and set them in
the back-end.
Thanks,
Kugan
gcc/ChangeLog:
2017-09-12 Kugan Vivekanandarajah <kug...@linaro.org>
* loop-unroll.c (decide_unroll_constant_iterations): Use new params.
(decide_unroll_runtime_iterations): Likewise.
(decide_unroll_stupid): Likewise.
* params.def (DEFPARAM): Separate and add new params for rtl unroller.
From a899caf9f82767de3db556225b28dc52a81d5967 Mon Sep 17 00:00:00 2001
From: Kugan Vivekanandarajah <kugan.vivekanandara...@linaro.org>
Date: Mon, 14 Aug 2017 10:12:09 +1000
Subject: [PATCH 1/5] add parms for rtl unroller
---
gcc/loop-unroll.c | 24 ++++++++++++------------
gcc/params.def | 17 +++++++++++++++++
2 files changed, 29 insertions(+), 12 deletions(-)
diff --git a/gcc/loop-unroll.c b/gcc/loop-unroll.c
index 84145bb..871558c 100644
--- a/gcc/loop-unroll.c
+++ b/gcc/loop-unroll.c
@@ -360,13 +360,13 @@ decide_unroll_constant_iterations (struct loop *loop, int flags)
/* nunroll = total number of copies of the original loop body in
unrolled loop (i.e. if it is 2, we have to duplicate loop body once. */
- nunroll = PARAM_VALUE (PARAM_MAX_UNROLLED_INSNS) / loop->ninsns;
+ nunroll = PARAM_VALUE (PARAM_MAX_UNROLLEDP_INSNS) / loop->ninsns;
nunroll_by_av
- = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLED_INSNS) / loop->av_ninsns;
+ = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLEDP_INSNS) / loop->av_ninsns;
if (nunroll > nunroll_by_av)
nunroll = nunroll_by_av;
- if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLL_TIMES))
- nunroll = PARAM_VALUE (PARAM_MAX_UNROLL_TIMES);
+ if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLLP_TIMES))
+ nunroll = PARAM_VALUE (PARAM_MAX_UNROLLP_TIMES);
if (targetm.loop_unroll_adjust)
nunroll = targetm.loop_unroll_adjust (nunroll, loop);
@@ -664,12 +664,12 @@ decide_unroll_runtime_iterations (struct loop *loop, int flags)
/* nunroll = total number of copies of the original loop body in
unrolled loop (i.e. if it is 2, we have to duplicate loop body once. */
- nunroll = PARAM_VALUE (PARAM_MAX_UNROLLED_INSNS) / loop->ninsns;
- nunroll_by_av = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLED_INSNS) / loop->av_ninsns;
+ nunroll = PARAM_VALUE (PARAM_MAX_UNROLLEDP_INSNS) / loop->ninsns;
+ nunroll_by_av = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLEDP_INSNS) / loop->av_ninsns;
if (nunroll > nunroll_by_av)
nunroll = nunroll_by_av;
- if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLL_TIMES))
- nunroll = PARAM_VALUE (PARAM_MAX_UNROLL_TIMES);
+ if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLLP_TIMES))
+ nunroll = PARAM_VALUE (PARAM_MAX_UNROLLP_TIMES);
if (targetm.loop_unroll_adjust)
nunroll = targetm.loop_unroll_adjust (nunroll, loop);
@@ -1158,13 +1158,13 @@ decide_unroll_stupid (struct loop *loop, int flags)
/* nunroll = total number of copies of the original loop body in
unrolled loop (i.e. if it is 2, we have to duplicate loop body once. */
- nunroll = PARAM_VALUE (PARAM_MAX_UNROLLED_INSNS) / loop->ninsns;
+ nunroll = PARAM_VALUE (PARAM_MAX_UNROLLEDP_INSNS) / loop->ninsns;
nunroll_by_av
- = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLED_INSNS) / loop->av_ninsns;
+ = PARAM_VALUE (PARAM_MAX_AVERAGE_UNROLLEDP_INSNS) / loop->av_ninsns;
if (nunroll > nunroll_by_av)
nunroll = nunroll_by_av;
- if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLL_TIMES))
- nunroll = PARAM_VALUE (PARAM_MAX_UNROLL_TIMES);
+ if (nunroll > (unsigned) PARAM_VALUE (PARAM_MAX_UNROLLP_TIMES))
+ nunroll = PARAM_VALUE (PARAM_MAX_UNROLLP_TIMES);
if (targetm.loop_unroll_adjust)
nunroll = targetm.loop_unroll_adjust (nunroll, loop);
diff --git a/gcc/params.def b/gcc/params.def
index 805302b..c8b0a2b 100644
--- a/gcc/params.def
+++ b/gcc/params.def
@@ -302,6 +302,23 @@ DEFPARAM(PARAM_MAX_PEELED_INSNS,
"max-peeled-insns",
"The maximum number of insns of a peeled loop.",
100, 0, 0)
+
+DEFPARAM(PARAM_MAX_UNROLLEDP_INSNS,
+ "max-partial-unrolled-insns",
+ "The maximum number of instructions to consider to unroll in a loop by rtl unroller.",
+ 100, 0, 0)
+/* This parameter limits how many times the loop is unrolled depending
+ on number of insns really executed in each iteration. */
+DEFPARAM(PARAM_MAX_AVERAGE_UNROLLEDP_INSNS,
+ "max-partial-average-unrolled-insns",
+ "The maximum number of instructions to consider to unroll in a loop on average by rtl unroller.",
+ 40, 0, 0)
+/* The maximum number of unrollings of a single loop. */
+DEFPARAM(PARAM_MAX_UNROLLP_TIMES,
+ "max-partial-unroll-times",
+ "The maximum number of unrollings of a single loop by rtl unroller.",
+ 4, 0, 0)
+
/* The maximum number of peelings of a single loop. */
DEFPARAM(PARAM_MAX_PEEL_TIMES,
"max-peel-times",
--
2.7.4
