https://gcc.gnu.org/g:25256ec1df10f2eb183e1c1ab0c890e9fdd94384
commit r15-7625-g25256ec1df10f2eb183e1c1ab0c890e9fdd94384
Author: Pan Li <pan2...@intel.com>
Date: Wed Feb 19 09:37:51 2025 +0800
Vect: Fix ICE when vect_verify_loop_lens acts on relevant mode [PR116351]
This patch would like to fix the ICE similar as below, assump we have
sample code:
1 │ int a, b, c;
2 │ short d, e, f;
3 │ long g (long h) { return h; }
4 │
5 │ void i () {
6 │ for (; b; ++b) {
7 │ f = 5 >> a ? d : d << a;
8 │ e &= c | g(f);
9 │ }
10 │ }
It will ice when compile with -O3 -march=rv64gc_zve64f -mrvv-vector-bits=zvl
during GIMPLE pass: vect
pr116351-1.c: In function ‘i’:
pr116351-1.c:8:6: internal compiler error: in get_len_load_store_mode,
at optabs-tree.cc:655
8 | void i () {
| ^
0x44d6b9d internal_error(char const*, ...)
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/diagnostic-global-context.cc:517
0x44a26a6 fancy_abort(char const*, int, char const*)
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/diagnostic.cc:1722
0x19e4309 get_len_load_store_mode(machine_mode, bool, internal_fn*,
vec<int, va_heap, vl_ptr>*)
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/optabs-tree.cc:655
0x1fada40 vect_verify_loop_lens
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/tree-vect-loop.cc:1566
0x1fb2b07 vect_analyze_loop_2
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/tree-vect-loop.cc:3037
0x1fb4302 vect_analyze_loop_1
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/tree-vect-loop.cc:3478
0x1fb4e9a vect_analyze_loop(loop*, gimple*, vec_info_shared*)
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/tree-vect-loop.cc:3638
0x203c2dc try_vectorize_loop_1
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/tree-vectorizer.cc:1095
0x203c839 try_vectorize_loop
/home/pli/gcc/111/riscv-gnu-toolchain/gcc/__RISC-V_BUILD__/../gcc/tree-vectorizer.cc:1212
0x203cb2c execute
During vectorization the override_widen pattern matched and then will get
DImode
as vector_mode in loop_info. After that the loop_vinfo will step in
vect_analyze_xx
with below flow:
vect_analyze_loop_2
|- vect_pattern_recog // over-widening and set loop_vinfo->vector_mode to
DImode
|- ...
|- vect_analyze_loop_operations
|- stmt_info->def_type == vect_reduction_def
|- stmt_info->slp_type == pure_slp
|- vectorizable_lc_phi // Not Hit
|- vectorizable_induction // Not Hit
|- vectorizable_reduction // Not Hit
|- vectorizable_recurr // Not Hit
|- vectorizable_live_operation // Not Hit
|- vect_analyze_stmt
|- stmt_info->relevant == vect_unused_in_scope
|- stmt_info->live == false
|- p pattern_stmt_info == (stmt_vec_info) 0x0
|- return opt_result::success ();
OR
|- PURE_SLP_STMT (stmt_info) && !node then dump "handled only by SLP
analysis\n"
|- Early return opt_result::success ();
|- vectorizable_load/store/call_convert/... // Not Hit
|- LOOP_VINFO_CAN_USE_PARTIAL_VECTORS_P &&
!LOOP_VINFO_MASKS(loop_vinfo).is_empty ()
|- vect_verify_loop_lens (loop_vinfo)
|- assert (VECTOR_MODE_P (loop_vinfo->vector_mode); // Hit assert
result in ICE
Finally, the DImode in loop_vinfo will hit the assert (VECTOR_MODE_P (mode))
in vect_verify_loop_lens. This patch would like to return false
directly if the loop_vinfo has relevant mode like DImode for the ICE
fix, but still may have mis-optimization for similar cases. We will try
to cover that in separated patches.
The below test suites are passed for this patch.
* The rv64gcv fully regression test.
* The x86 bootstrap test.
* The x86 fully regression test.
PR middle-end/116351
gcc/ChangeLog:
* tree-vect-loop.cc (vect_verify_loop_lens): Return false if the
loop_vinfo has relevant mode such as DImode.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/rvv/base/pr116351-1.c: New test.
* gcc.target/riscv/rvv/base/pr116351-2.c: New test.
* gcc.target/riscv/rvv/base/pr116351.h: New test.
Signed-off-by: Pan Li <pan2...@intel.com>
Diff:
---
gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-1.c | 5 +++++
gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-2.c | 5 +++++
gcc/testsuite/gcc.target/riscv/rvv/base/pr116351.h | 18 ++++++++++++++++++
gcc/tree-vect-loop.cc | 3 +++
4 files changed, 31 insertions(+)
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-1.c
b/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-1.c
new file mode 100644
index 000000000000..f58fedfeaf1f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-1.c
@@ -0,0 +1,5 @@
+/* Test that we do not have ice when compile */
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_zve32x -mabi=lp64d -O3 -ftree-vectorize" } */
+
+#include "pr116351.h"
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-2.c
b/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-2.c
new file mode 100644
index 000000000000..e1f46b745e25
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351-2.c
@@ -0,0 +1,5 @@
+/* Test that we do not have ice when compile */
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_zve32f -mabi=lp64d -O3 -ftree-vectorize" } */
+
+#include "pr116351.h"
diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351.h
b/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351.h
new file mode 100644
index 000000000000..25bd0ec65e0d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/pr116351.h
@@ -0,0 +1,18 @@
+#ifndef PR116351_H
+#define PR116351_H
+
+#define T long
+
+int a, b, c;
+short d, e, f;
+
+T g (T h) { return h; }
+
+void i () {
+ for (; b; ++b) {
+ f = 5 >> a ? d : d << a;
+ e &= c | g(f);
+ }
+}
+
+#endif
diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 07b19a22d42c..b279ebe2793b 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -1562,6 +1562,9 @@ vect_verify_loop_lens (loop_vec_info loop_vinfo)
if (LOOP_VINFO_LENS (loop_vinfo).is_empty ())
return false;
+ if (!VECTOR_MODE_P (loop_vinfo->vector_mode))
+ return false;
+
machine_mode len_load_mode, len_store_mode;
if (!get_len_load_store_mode (loop_vinfo->vector_mode, true)
.exists (&len_load_mode))
