From: Robin Dapp <rdapp@ventanamicro.com>
Date: Tue, 8 Jul 2025 09:35:12 +0000 (+0200)
Subject: RISC-V: Do not use vsetivli for THeadVector.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dab5951af891c58aa4dd60755edb49df882b680a;p=thirdparty%2Fgcc.git

RISC-V: Do not use vsetivli for THeadVector.

In emit_vlmax_insn_lra we use a vsetivli for an immediate AVL.
XTHeadVector does not support this, so guard appropriately.

	PR target/120461

gcc/ChangeLog:

	* config/riscv/riscv-v.cc (emit_vlmax_insn_lra): Do not emit
	vsetivli for XTHeadVector.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/xtheadvector/pr120461.c: New test.
---

diff --git a/gcc/config/riscv/riscv-v.cc b/gcc/config/riscv/riscv-v.cc
index a5ab8dd4e2f..22d194909cf 100644
--- a/gcc/config/riscv/riscv-v.cc
+++ b/gcc/config/riscv/riscv-v.cc
@@ -408,7 +408,7 @@ emit_vlmax_insn_lra (unsigned icode, unsigned insn_flags, rtx *ops, rtx vl)
   gcc_assert (!can_create_pseudo_p ());
   machine_mode mode = GET_MODE (ops[0]);
 
-  if (imm_avl_p (mode))
+  if (imm_avl_p (mode) && !TARGET_XTHEADVECTOR)
     {
       /* Even though VL is a real hardreg already allocated since
 	 it is post-RA now, we still gain benefits that we emit
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/xtheadvector/pr120461.c b/gcc/testsuite/gcc.target/riscv/rvv/xtheadvector/pr120461.c
new file mode 100644
index 00000000000..69391570970
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/xtheadvector/pr120461.c
@@ -0,0 +1,6 @@
+/* { dg-do compile } */
+/* { dg-options "-mcpu=xt-c920 -mrvv-vector-bits=zvl -fzero-call-used-regs=all" */
+
+void
+foo ()
+{}