[PATCH 19/61] Add support for a limit for inlining memcpy

[Aleksandar Rakic]

From: Matthew Fortune <matthew.fort...@imgtec.com>

Expose it with an option: -mblockmov-limit. A memcpy strictly less than
this value will be considered for inlining.

gcc/ChangeLog:

        * config/mips/mips.cc (mips_expand_block_move): Add support to
        control size of inlined memcpy.
        * config/mips/mips.opt (mblockmov-limit): New option.

Cherry-picked cf1e4960a4f80301e4c8f71a35cbbc8fef1ce6fd
from https://github.com/MIPS/gcc

Signed-off-by: Matthew Fortune <matthew.fort...@imgtec.com>
Signed-off-by: Faraz Shahbazker <fshahbaz...@wavecomp.com>
Signed-off-by: Aleksandar Rakic <aleksandar.ra...@htecgroup.com>
---
 gcc/config/mips/mips.cc  | 21 ++++++++++++---------
 gcc/config/mips/mips.opt |  3 +++
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/gcc/config/mips/mips.cc b/gcc/config/mips/mips.cc
index 32fe62ce79b..d9c913f2e23 100644
--- a/gcc/config/mips/mips.cc
+++ b/gcc/config/mips/mips.cc
@@ -9360,16 +9360,19 @@ mips_expand_block_move (rtx dest, rtx src, rtx length)
          || MEM_ALIGN (dest) < MIPS_MIN_MOVE_MEM_ALIGN))
     return false;
 
-  if (INTVAL (length) <= MIPS_MAX_MOVE_BYTES_PER_LOOP_ITER)
+  if (mips_movmem_limit == -1 || INTVAL (length) < mips_movmem_limit)
     {
-      mips_block_move_straight (dest, src, INTVAL (length));
-      return true;
-    }
-  else if (optimize)
-    {
-      mips_block_move_loop (dest, src, INTVAL (length),
-                           MIPS_MAX_MOVE_BYTES_PER_LOOP_ITER);
-      return true;
+      if (INTVAL (length) <= MIPS_MAX_MOVE_BYTES_PER_LOOP_ITER)
+  {
+    mips_block_move_straight (dest, src, INTVAL (length));
+    return true;
+  }
+      else if (optimize)
+  {
+    mips_block_move_loop (dest, src, INTVAL (length),
+                         MIPS_MAX_MOVE_BYTES_PER_LOOP_ITER);
+    return true;
+  }
     }
 
   return false;
diff --git a/gcc/config/mips/mips.opt b/gcc/config/mips/mips.opt
index 012ca91560f..a4b93de924d 100644
--- a/gcc/config/mips/mips.opt
+++ b/gcc/config/mips/mips.opt
@@ -556,3 +556,6 @@ munique-sections=FILE   Use to specify sections that should 
be made unique.
 mfunc-opt-list=
 Target RejectNegative Joined Var(mips_func_opt_list_file) Init(0) Defer
 mfunc-opt-list=FILE    Use to specify per function optimizations.
+
+mblockmov-limit=
+Target RejectNegative Undocumented Joined UInteger Var(mips_movmem_limit) 
Init(-1)
-- 
2.34.1