Currently if the rtl is either an arithmetic or an unary
rtl, noce_can_force_operand checks to see if there is an
optab for that rtl code. This works for more things except
on some targets they have a ss_minus instruction but don't
implement the optab for it. In the case of arm you can
generate a ss_minus with a builtin and then when it comes
to trying to do ifcvt, force_operand fails over.
In this case the optab, sssub was only supported for
fixed-point modes before and it was working as code_to_optab
would return there was not optabs. But after r15-1030-gabe6d39365476e,
the optab will be return. What the backend is doing is correct and will
most likely happen with other rtl codes/optabs later on.
To fix this instead of just returning true if the optab exists, we need
to check if the optab entry for the mode exists.
PR rtl-optimization/122170
gcc/ChangeLog:
* ifcvt.cc (noce_can_force_operand): Don't only check if
there is an optab for the code check the entry for the
mode is non-null. Handle non integral div by checking
optab like force_operand does.
Signed-off-by: Andrew Pinski <[email protected]>
(cherry picked from commit 40f6ae016571ce6ea5951f406c4be7ff84914fbc)
---
gcc/ifcvt.cc | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/gcc/ifcvt.cc b/gcc/ifcvt.cc
index da8631f3c59..c34072f36fe 100644
--- a/gcc/ifcvt.cc
+++ b/gcc/ifcvt.cc
@@ -925,13 +925,19 @@ noce_can_force_operand (rtx x)
switch (GET_CODE (x))
{
case MULT:
- case DIV:
case MOD:
case UDIV:
case UMOD:
return true;
+ case DIV:
+ if (INTEGRAL_MODE_P (GET_MODE (x)))
+ return true;
+ /* FALLTHRU */
default:
- return code_to_optab (GET_CODE (x));
+ auto optab = code_to_optab (GET_CODE (x));
+ if (!optab)
+ return false;
+ return optab_handler (optab, GET_MODE (x));
}
}
if (UNARY_P (x))
@@ -951,7 +957,10 @@ noce_can_force_operand (rtx x)
case UNSIGNED_FLOAT:
return true;
default:
- return code_to_optab (GET_CODE (x));
+ auto optab = code_to_optab (GET_CODE (x));
+ if (!optab)
+ return false;
+ return optab_handler (optab, GET_MODE (x));
}
}
return false;
--
2.43.0
