From c864ffe615424de08abfe271fee7dc815c93bd21 Mon Sep 17 00:00:00 2001
From: Robin Dapp <rdapp.gcc@gmail.com>
Date: Mon, 13 Jan 2025 17:19:42 -0700
Subject: [PATCH] RISC-V: Expand shift count in Xmode in interleave pattern.
Hi,
currently ssa-dse-1.C ICEs because expand_simple_binop returns NULL
when building the scalar that is used to IOR two interleaving
sequences.
That's because we try to emit a shift in HImode. This patch shifts in
Xmode and then lowpart-subregs the result to HImode.
Regtested on rv64gcv_zvl512b.
Regards
Robin
gcc/ChangeLog:
* config/riscv/riscv-v.cc (expand_const_vector): Shift in Xmode.
---
gcc/config/riscv/riscv-v.cc | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/gcc/config/riscv/riscv-v.cc b/gcc/config/riscv/riscv-v.cc
index 9926a7b63bb5..3735a5ba6594 100644
--- a/gcc/config/riscv/riscv-v.cc
+++ b/gcc/config/riscv/riscv-v.cc
@@ -1505,10 +1505,11 @@ expand_const_vector (rtx target, rtx src)
{
/* { 1, 1, 2, 1, ... }. */
rtx scalar = expand_simple_binop (
- new_smode, ASHIFT,
- gen_int_mode (rtx_to_poly_int64 (base2), new_smode),
- gen_int_mode (builder.inner_bits_size (), new_smode),
+ Xmode, ASHIFT,
+ gen_int_mode (rtx_to_poly_int64 (base2), Xmode),
+ gen_int_mode (builder.inner_bits_size (), Xmode),
NULL_RTX, false, OPTAB_DIRECT);
+ scalar = simplify_gen_subreg (new_smode, scalar, Xmode, 0);
rtx tmp2 = gen_reg_rtx (new_mode);
rtx ior_ops[] = {tmp2, tmp1, scalar};
emit_vlmax_insn (code_for_pred_scalar (IOR, new_mode),
--
GitLab