Currently for an unsigned 16-bit comparison between memory and an
immediate where the high bit is set, a clc is emitted. This is because
the constant is created for mode HI and therefore sign extended. This
means constraint D does not hold anymore. Since the mode already
restricts the immediate to 16 bit, it is enough to make use of
constraint n and chop of the high bits in the output template.
Bootstrapped and regtested on s390. Ok for mainline?
gcc/ChangeLog:
* config/s390/s390.md (*cmphi_ccu): For immediate operand 1 make
use of constraint n instead of D and chop of high bits in the
output template.
---
gcc/config/s390/s390.md | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/gcc/config/s390/s390.md b/gcc/config/s390/s390.md
index 3f29ba21442..777a20f8e77 100644
--- a/gcc/config/s390/s390.md
+++ b/gcc/config/s390/s390.md
@@ -1355,13 +1355,13 @@
(define_insn "*cmphi_ccu"
[(set (reg CC_REGNUM)
(compare (match_operand:HI 0 "nonimmediate_operand" "d,d,Q,Q,BQ")
- (match_operand:HI 1 "general_operand" "Q,S,D,BQ,Q")))]
+ (match_operand:HI 1 "general_operand" "Q,S,n,BQ,Q")))]
"s390_match_ccmode (insn, CCUmode)
&& !register_operand (operands[1], HImode)"
"@
clm\t%0,3,%S1
clmy\t%0,3,%S1
- clhhsi\t%0,%1
+ clhhsi\t%0,%x1
#
#"
[(set_attr "op_type" "RS,RSY,SIL,SS,SS")
--
2.41.0
