diff mbox series

tree-cfg: Fix misleading error message in verify_gimple_assign_single

Message ID CAJ=gGT37r+cbCfdcvS1naPELSSyeveg_ueSdzNB-dS+8AaybHA@mail.gmail.com
State Accepted
Headers
Series tree-cfg: Fix misleading error message in verify_gimple_assign_single |

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snail/gcc-patch-check success Github commit url

Commit Message

xndcn Dec. 10, 2023, 2:59 p.m. UTC 
  Hi, I am a newbie in GCC, and I do not have access to git repo.

I found some misleading error messages in verify_gimple_assign_single
function of tree-cfg.cc. It prompt error "invalid RHS for gimple memory
store: ", but it checks lhs in fact.

Comments

xndcn Dec. 10, 2023, 3:20 p.m. UTC | #1 
Sorry about the attachment, re-paste here
Richard Biener Dec. 11, 2023, 7:56 a.m. UTC | #2 
On Sun, Dec 10, 2023 at 4:00 PM xndcn <xndchn@gmail.com> wrote:
>
> Hi, I am a newbie in GCC, and I do not have access to git repo.
>
> I found some misleading error messages in verify_gimple_assign_single function of tree-cfg.cc. It prompt error "invalid RHS for gimple memory store: ", but it checks lhs in fact.

it might be a bit confusing but it's correct.  There is a store
because !is_gimple_reg (lhs)
and the only case !is_gimple_reg (rhs1) is correct is when this is an aggregate
copy (!is_gimple_reg_type (TREE_TYPE (lhs))).  Otherwise the _RHS_ needs to be
a register.

Richard.
xndcn Dec. 11, 2023, 11:38 a.m. UTC | #3 
Got it, thanks! It is really confusing >,<
What about the first one? For case MEM_REF.

在 2023年12月11日星期一，Richard Biener <richard.guenther@gmail.com> 写道：

> On Sun, Dec 10, 2023 at 4:00 PM xndcn <xndchn@gmail.com> wrote:
> >
> > Hi, I am a newbie in GCC, and I do not have access to git repo.
> >
> > I found some misleading error messages in verify_gimple_assign_single
> function of tree-cfg.cc. It prompt error "invalid RHS for gimple memory
> store: ", but it checks lhs in fact.
>
> it might be a bit confusing but it's correct.  There is a store
> because !is_gimple_reg (lhs)
> and the only case !is_gimple_reg (rhs1) is correct is when this is an
> aggregate
> copy (!is_gimple_reg_type (TREE_TYPE (lhs))).  Otherwise the _RHS_ needs
> to be
> a register.
>
> Richard.
>
Richard Biener Dec. 11, 2023, 11:39 a.m. UTC | #4 
On Mon, Dec 11, 2023 at 12:39 PM xndcn <xndchn@gmail.com> wrote:
>
> Got it, thanks! It is really confusing >,<
> What about the first one? For case MEM_REF.

The same - the LHS determines this is a store, if it is the
RHS is invalid as diagnosed (it needs to go through a
temporary).

Richard.



> 在 2023年12月11日星期一，Richard Biener <richard.guenther@gmail.com> 写道：
>>
>> On Sun, Dec 10, 2023 at 4:00 PM xndcn <xndchn@gmail.com> wrote:
>> >
>> > Hi, I am a newbie in GCC, and I do not have access to git repo.
>> >
>> > I found some misleading error messages in verify_gimple_assign_single function of tree-cfg.cc. It prompt error "invalid RHS for gimple memory store: ", but it checks lhs in fact.
>>
>> it might be a bit confusing but it's correct.  There is a store
>> because !is_gimple_reg (lhs)
>> and the only case !is_gimple_reg (rhs1) is correct is when this is an aggregate
>> copy (!is_gimple_reg_type (TREE_TYPE (lhs))).  Otherwise the _RHS_ needs to be
>> a register.
>>
>> Richard.
xndcn Dec. 11, 2023, 12:02 p.m. UTC | #5 
Thanks, now I have totally understand! I think it deserves a clearer
prompt, but I do not have a better idea currently. So forget it, thanks!

在 2023年12月11日星期一，Richard Biener <richard.guenther@gmail.com> 写道：

> On Mon, Dec 11, 2023 at 12:39 PM xndcn <xndchn@gmail.com> wrote:
> >
> > Got it, thanks! It is really confusing >,<
> > What about the first one? For case MEM_REF.
>
> The same - the LHS determines this is a store, if it is the
> RHS is invalid as diagnosed (it needs to go through a
> temporary).
>
> Richard.
>
>
>
> > 在 2023年12月11日星期一，Richard Biener <richard.guenther@gmail.com> 写道：
> >>
> >> On Sun, Dec 10, 2023 at 4:00 PM xndcn <xndchn@gmail.com> wrote:
> >> >
> >> > Hi, I am a newbie in GCC, and I do not have access to git repo.
> >> >
> >> > I found some misleading error messages in verify_gimple_assign_single
> function of tree-cfg.cc. It prompt error "invalid RHS for gimple memory
> store: ", but it checks lhs in fact.
> >>
> >> it might be a bit confusing but it's correct.  There is a store
> >> because !is_gimple_reg (lhs)
> >> and the only case !is_gimple_reg (rhs1) is correct is when this is an
> aggregate
> >> copy (!is_gimple_reg_type (TREE_TYPE (lhs))).  Otherwise the _RHS_
> needs to be
> >> a register.
> >>
> >> Richard.
>
diff mbox series

Patch

From 72fc4abe635c3e35ac31457aeba92b528f0574fe Mon Sep 17 00:00:00 2001
From: xndcn <xndchn@gmail.com>
Date: Sun, 10 Dec 2023 22:38:16 +0800
Subject: [PATCH] tree-cfg: Fix misleading error message in
 verify_gimple_assign_single.

gcc/ChangeLog:

	* tree-cfg.cc (verify_gimple_assign_single): Fix misleading error, from "invalid LHS ..." to "invalid RHS ..."

Signed-off-by: xndcn <xndchn@gmail.com>
---
 gcc/tree-cfg.cc | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
index d784b9115..f041786b3 100644
--- a/gcc/tree-cfg.cc
+++ b/gcc/tree-cfg.cc
@@ -4695,7 +4695,7 @@  verify_gimple_assign_single (gassign *stmt)
       if (!is_gimple_reg (lhs)
 	  && is_gimple_reg_type (TREE_TYPE (lhs)))
 	{
-	  error ("invalid RHS for gimple memory store: %qs", code_name);
+	  error ("invalid LHS for gimple memory store: %qs", code_name);
 	  debug_generic_stmt (lhs);
 	  debug_generic_stmt (rhs1);
 	  return true;
@@ -4721,7 +4721,10 @@  verify_gimple_assign_single (gassign *stmt)
 	  && !is_gimple_reg (rhs1)
 	  && is_gimple_reg_type (TREE_TYPE (lhs)))
 	{
-	  error ("invalid RHS for gimple memory store: %qs", code_name);
+	  if (!is_gimple_reg (rhs1))
+	    error ("invalid RHS for gimple memory store: %qs", code_name);
+	  else
+	    error ("invalid LHS for gimple memory store: %qs", code_name);
 	  debug_generic_stmt (lhs);
 	  debug_generic_stmt (rhs1);
 	  return true;
-- 
2.25.1