The bare CONST_INT inside the CCmode IF_THEN_ELSE is causing combine to make
incorrect simplifications. At this stage it feels safer to wrap the CONST_INT
inside of an UNSPEC than make more generic changes to combine.
But we should definitely investigate combine's CCmode issues for gcc7.
Ok?
r~
* config/aarch64/aarch64.md (UNSPEC_NZCV): New.
(ccmp<mode>, fccmp<mode>, fccmpe<mode>): Use it.
diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index 2f543aa..71fc514 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -129,6 +129,7 @@
UNSPEC_RSQRT
UNSPEC_RSQRTE
UNSPEC_RSQRTS
+ UNSPEC_NZCV
])
(define_c_enum "unspecv" [
@@ -280,7 +281,7 @@
(compare:CC
(match_operand:GPI 2 "register_operand" "r,r,r")
(match_operand:GPI 3 "aarch64_ccmp_operand" "r,Uss,Usn"))
- (match_operand 5 "immediate_operand")))]
+ (unspec:CC [(match_operand 5 "immediate_operand")] UNSPEC_NZCV)))]
""
"@
ccmp\\t%<w>2, %<w>3, %k5, %m4
@@ -298,7 +299,7 @@
(compare:CCFP
(match_operand:GPF 2 "register_operand" "w")
(match_operand:GPF 3 "register_operand" "w"))
- (match_operand 5 "immediate_operand")))]
+ (unspec:CCFP [(match_operand 5 "immediate_operand")] UNSPEC_NZCV)))]
"TARGET_FLOAT"
"fccmp\\t%<s>2, %<s>3, %k5, %m4"
[(set_attr "type" "fcmp<s>")]
@@ -313,7 +314,7 @@
(compare:CCFPE
(match_operand:GPF 2 "register_operand" "w")
(match_operand:GPF 3 "register_operand" "w"))
- (match_operand 5 "immediate_operand")))]
+ (unspec:CCFPE [(match_operand 5 "immediate_operand")] UNSPEC_NZCV)))]
"TARGET_FLOAT"
"fccmpe\\t%<s>2, %<s>3, %k5, %m4"
[(set_attr "type" "fcmp<s>")]
