On 8/8/23 21:05, pan2...@intel.com wrote:
From: Pan Li <pan2...@intel.com>
In same cases, like gcc/testsuite/gcc.dg/pr78148.c in RISC-V, there will
be only 1 operand when SET_SRC in create_pre_exit. For example as below.
(insn 13 9 14 2 (clobber (reg/i:TI 10 a0))
"gcc/testsuite/gcc.dg/pr78148.c":24:1 -1
(expr_list:REG_UNUSED (reg/i:TI 10 a0)
(nil)))
Unfortunately, SET_SRC requires at least 2 operands and then Segment
Fault here. For SH4 part result in Segment Fault, it looks like only
valid when the return_copy_pat is load or something like that. Thus,
this patch try to fix it by ingnoring the CLOBBER insn for SH4.
Signed-off-by: Pan Li <pan2...@intel.com>
gcc/ChangeLog:
* mode-switching.cc (create_pre_exit): Add CLOBBER check.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/mode-switch-ice-1.c: New test.
---
gcc/mode-switching.cc | 2 +-
.../gcc.target/riscv/mode-switch-ice-1.c | 22 +++++++++++++++++++
2 files changed, 23 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.target/riscv/mode-switch-ice-1.c
diff --git a/gcc/mode-switching.cc b/gcc/mode-switching.cc
index 64ae2bc29c3..b034cf7d437 100644
--- a/gcc/mode-switching.cc
+++ b/gcc/mode-switching.cc
@@ -392,7 +392,7 @@ create_pre_exit (int n_entities, int *entity_map, const int
*num_modes)
&& mode != targetm.mode_switching.exit (e))
break;
}
- if (j >= 0)
+ if (j >= 0 && GET_CODE (return_copy_pat) != CLOBBER)
{
/* __builtin_return emits a sequence of loads to all
return registers. One of them might require
I'd tend to prefer to guard the code a bit later so that the test for
CLOBBERS is closer to the point where they're not allowed. ie
/* For the SH4, floating point loads depend on fpscr,
thus we might need to put the final mode switch
after the return value copy. That is still OK,
because a floating point return value does not
conflict with address reloads. */
if (copy_start >= ret_start
&& copy_start + copy_num <= ret_end
&& OBJECT_P (SET_SRC (return_copy_pat)))
forced_late_switch = true;
break;
I'd put it in that code. Probably something like
&& GET_CODE (return_copy_pat) = SET
&& OBJECT_P (SET_SRC (return_copy_pat)))
That way we make it clear that we should only be looking at SET_SRC of
an actual SET.
Is there some reason you put the guard earlier?
jeff
