https://gcc.gnu.org/g:e0700fbe35286d31fe64782b255c8d2caec673dc
commit r15-1401-ge0700fbe35286d31fe64782b255c8d2caec673dc
Author: Richard Sandiford <richard.sandif...@arm.com>
Date: Tue Jun 18 12:22:32 2024 +0100
Add force_highpart_subreg
This patch adds a force_highpart_subreg to go along with the
recently added force_lowpart_subreg.
gcc/
* explow.h (force_highpart_subreg): Declare.
* explow.cc (force_highpart_subreg): New function.
* builtins.cc (expand_builtin_issignaling): Use it.
* expmed.cc (emit_store_flag_1): Likewise.
Diff:
---
gcc/builtins.cc | 15 ++++-----------
gcc/explow.cc | 14 ++++++++++++++
gcc/explow.h | 1 +
gcc/expmed.cc | 4 +---
4 files changed, 20 insertions(+), 14 deletions(-)
diff --git a/gcc/builtins.cc b/gcc/builtins.cc
index bde517b639e8..d467d1697b45 100644
--- a/gcc/builtins.cc
+++ b/gcc/builtins.cc
@@ -2835,9 +2835,7 @@ expand_builtin_issignaling (tree exp, rtx target)
it is, working on the DImode high part is usually better. */
if (!MEM_P (temp))
{
- if (rtx t = simplify_gen_subreg (imode, temp, fmode,
- subreg_highpart_offset (imode,
- fmode)))
+ if (rtx t = force_highpart_subreg (imode, temp, fmode))
hi = t;
else
{
@@ -2845,9 +2843,7 @@ expand_builtin_issignaling (tree exp, rtx target)
if (int_mode_for_mode (fmode).exists (&imode2))
{
rtx temp2 = gen_lowpart (imode2, temp);
- poly_uint64 off = subreg_highpart_offset (imode, imode2);
- if (rtx t = simplify_gen_subreg (imode, temp2,
- imode2, off))
+ if (rtx t = force_highpart_subreg (imode, temp2, imode2))
hi = t;
}
}
@@ -2938,8 +2934,7 @@ expand_builtin_issignaling (tree exp, rtx target)
it is, working on DImode parts is usually better. */
if (!MEM_P (temp))
{
- hi = simplify_gen_subreg (imode, temp, fmode,
- subreg_highpart_offset (imode, fmode));
+ hi = force_highpart_subreg (imode, temp, fmode);
lo = force_lowpart_subreg (imode, temp, fmode);
if (!hi || !lo)
{
@@ -2947,9 +2942,7 @@ expand_builtin_issignaling (tree exp, rtx target)
if (int_mode_for_mode (fmode).exists (&imode2))
{
rtx temp2 = gen_lowpart (imode2, temp);
- hi = simplify_gen_subreg (imode, temp2, imode2,
- subreg_highpart_offset (imode,
- imode2));
+ hi = force_highpart_subreg (imode, temp2, imode2);
lo = force_lowpart_subreg (imode, temp2, imode2);
}
}
diff --git a/gcc/explow.cc b/gcc/explow.cc
index 2a91cf76ea62..b4a0df89bc36 100644
--- a/gcc/explow.cc
+++ b/gcc/explow.cc
@@ -778,6 +778,20 @@ force_lowpart_subreg (machine_mode outermode, rtx op,
return force_subreg (outermode, op, innermode, byte);
}
+/* Try to return an rvalue expression for the OUTERMODE highpart of OP,
+ which has mode INNERMODE. Allow OP to be forced into a new register
+ if necessary.
+
+ Return null on failure. */
+
+rtx
+force_highpart_subreg (machine_mode outermode, rtx op,
+ machine_mode innermode)
+{
+ auto byte = subreg_highpart_offset (outermode, innermode);
+ return force_subreg (outermode, op, innermode, byte);
+}
+
/* If X is a memory ref, copy its contents to a new temp reg and return
that reg. Otherwise, return X. */
diff --git a/gcc/explow.h b/gcc/explow.h
index dd654649b068..de89e9e2933e 100644
--- a/gcc/explow.h
+++ b/gcc/explow.h
@@ -44,6 +44,7 @@ extern rtx force_reg (machine_mode, rtx);
extern rtx force_subreg (machine_mode, rtx, machine_mode, poly_uint64);
extern rtx force_lowpart_subreg (machine_mode, rtx, machine_mode);
+extern rtx force_highpart_subreg (machine_mode, rtx, machine_mode);
/* Return given rtx, copied into a new temp reg if it was in memory. */
extern rtx force_not_mem (rtx);
diff --git a/gcc/expmed.cc b/gcc/expmed.cc
index 1f68e7be721d..3b9475f5aa0b 100644
--- a/gcc/expmed.cc
+++ b/gcc/expmed.cc
@@ -5784,9 +5784,7 @@ emit_store_flag_1 (rtx target, enum rtx_code code, rtx
op0, rtx op1,
rtx op0h;
/* If testing the sign bit, can just test on high word. */
- op0h = simplify_gen_subreg (word_mode, op0, int_mode,
- subreg_highpart_offset (word_mode,
- int_mode));
+ op0h = force_highpart_subreg (word_mode, op0, int_mode);
tem = emit_store_flag (NULL_RTX, code, op0h, op1, word_mode,
unsignedp, normalizep);
}
