回复: RE: [PATCH] RISC-V: Fix ICE in riscv vector costs

[juzhe.zh...@rivai.ai]

I suggest open an PR with a PR id.



juzhe.zh...@rivai.ai
 
发件人： Demin Han
发送时间： 2024-03-07 15:39
收件人： juzhe.zh...@rivai.ai; gcc-patches
抄送： kito.cheng; pan2.li; jeffreyalaw
主题： RE: [PATCH] RISC-V: Fix ICE in riscv vector costs
OK.
Which is better for testcase name?
1.      ice-biggestmode.c or
2.      Report a bug and name the testcase with PR id
 
From: juzhe.zh...@rivai.ai <juzhe.zh...@rivai.ai> 
Sent: 2024年3月7日 15:20
To: Demin Han <demin....@starfivetech.com>; gcc-patches 
<gcc-patches@gcc.gnu.org>
Cc: kito.cheng <kito.ch...@gmail.com>; pan2.li <pan2...@intel.com>; jeffreyalaw 
<jeffreya...@gmail.com>
Subject: Re: [PATCH] RISC-V: Fix ICE in riscv vector costs
 
Could you plz add testcase ? I just noticed you didn't append a testcase (jpeg) 
in this patch.
 


juzhe.zh...@rivai.ai
 
From: demin.han
Date: 2024-03-07 13:54
To: gcc-patches
CC: juzhe.zhong; kito.cheng; pan2.li; jeffreyalaw
Subject: [PATCH] RISC-V: Fix ICE in riscv vector costs
The following code can result in ICE:
-march=rv64gcv_zba_zbb --param riscv-autovec-lmul=dynamic -O3
 
char *jpeg_difference7_input_buf;
void jpeg_difference7(int *diff_buf) {
  unsigned width;
  int samp, Rb;
  while (--width) {
    Rb = samp = *jpeg_difference7_input_buf;
    *diff_buf++ = -(int)(samp + (long)Rb >> 1);
  }
}
 
One biggest_mode update missed in one branch and trigger assertion fail.
gcc_assert (biggest_size >= mode_size);
 
Tested On RV64 and no regression.
 
gcc/ChangeLog:
 
* config/riscv/riscv-vector-costs.cc: Fix ICE
 
Signed-off-by: demin.han <demin....@starfivetech.com>
---
gcc/config/riscv/riscv-vector-costs.cc | 2 ++
1 file changed, 2 insertions(+)
 
diff --git a/gcc/config/riscv/riscv-vector-costs.cc 
b/gcc/config/riscv/riscv-vector-costs.cc
index 7c9840df4e9..f13a1296b31 100644
--- a/gcc/config/riscv/riscv-vector-costs.cc
+++ b/gcc/config/riscv/riscv-vector-costs.cc
@@ -413,6 +413,8 @@ compute_local_live_ranges (
  auto *r = get_live_range (live_ranges, arg);
  gcc_assert (r);
  (*r).second = MAX (point, (*r).second);
+   biggest_mode = get_biggest_mode (
+     biggest_mode, TYPE_MODE (TREE_TYPE (arg)));
}
    }
  else
-- 
2.44.0