LGTM.
juzhe.zh...@rivai.ai
From: Robin Dapp
Date: 2023-12-05 23:13
To: gcc-patches; palmer; Kito Cheng; jeffreyalaw; juzhe.zh...@rivai.ai
CC: rdapp.gcc
Subject: [PATCH] RISC-V: Add vec_init expander for masks [PR112854].
Hi,
PR112854 shows a problem on rv32 with zvl1024b. During the course of
expand_constructor we try to overlay/subreg a 64-element mask by a
scalar (Pmode) register. This works for zvle512b and its maximum of
32 elements but fails for rv32 and 64 elements.
To circumvent this this patch adds a vec_init expander for vector masks
by initializing a QImode vector and comparing that against 0. This
also ensures we don't do element initialization of masks.
Regards
Robin
gcc/ChangeLog:
PR target/112854
* config/riscv/autovec.md (vec_init<mode>qi): New expander.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/rvv/autovec/pr112854.c: New test.
---
gcc/config/riscv/autovec.md | 16 ++++++++++++++++
.../gcc.target/riscv/rvv/autovec/pr112854.c | 12 ++++++++++++
2 files changed, 28 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/autovec/pr112854.c
diff --git a/gcc/config/riscv/autovec.md b/gcc/config/riscv/autovec.md
index 3c4d68367f0..65ab76b3e0c 100644
--- a/gcc/config/riscv/autovec.md
+++ b/gcc/config/riscv/autovec.md
@@ -394,6 +394,22 @@ (define_expand "vec_init<mode><vel>"
}
)
+;; Provide a vec_init for mask registers by initializing
+;; a QImode vector and comparing it against 0.
+(define_expand "vec_init<mode>qi"
+ [(match_operand:VB 0 "register_operand")
+ (match_operand 1 "")]
+ "TARGET_VECTOR"
+ {
+ machine_mode qimode = riscv_vector::get_vector_mode
+ (QImode, GET_MODE_NUNITS (<MODE>mode)).require ();
+ rtx tmp = gen_reg_rtx (qimode);
+ riscv_vector::expand_vec_init (tmp, operands[1]);
+ riscv_vector::expand_vec_cmp (operands[0], NE, tmp, CONST0_RTX (qimode));
+ DONE;
+ }
+)
+
;; Slide an RVV vector left and insert a scalar into element 0.
(define_expand "vec_shl_insert_<mode>"
[(match_operand:VI 0 "register_operand")
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/autovec/pr112854.c
b/gcc/testsuite/gcc.target/riscv/rvv/autovec/pr112854.c
new file mode 100644
index 00000000000..8f7f13f9dc1
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/autovec/pr112854.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv32gcv_zvl1024b -mabi=ilp32d
--param=riscv-autovec-preference=fixed-vlmax" } */
+
+short a, b;
+void c(int d) {
+ for (; a; a--) {
+ b = 0;
+ for (; b <= 8; b++)
+ if (d)
+ break;
+ }
+}
--
2.43.0
