The aarch64_legitimate_constant_p tests for HIGH and CONST seem
to be the wrong way round: (high (const ...)) is valid rtl that
could be passed in, but (const (high ...)) isn't. As it stands,
we disallow anchor+offset but allow (high anchor+offset).
TBH I can't remember whether this caused a test failure or if it
was just something I noticed by inspection. Either way, the SVE port
adds more invalid (const ...)s and it doesn't make sense to test for
them before peeling the HIGH.
Tested on aarch64-linux-gnu. OK to install?
Richard
2018-01-04 Richard Sandiford <richard.sandif...@linaro.org>
gcc/
* config/aarch64/aarch64.c (aarch64_legitimate_constant_p): Fix
order of HIGH and CONST checks.
Index: gcc/config/aarch64/aarch64.c
===================================================================
--- gcc/config/aarch64/aarch64.c 2018-01-03 21:43:30.290452983 +0000
+++ gcc/config/aarch64/aarch64.c 2018-01-04 18:11:30.299730142 +0000
@@ -10449,6 +10449,9 @@ aarch64_legitimate_constant_p (machine_m
if (CONST_WIDE_INT_P (x))
return false;
+ if (GET_CODE (x) == HIGH)
+ x = XEXP (x, 0);
+
/* Do not allow const (plus (anchor_symbol, const_int)). */
if (GET_CODE (x) == CONST)
{
@@ -10460,9 +10463,6 @@ aarch64_legitimate_constant_p (machine_m
return false;
}
- if (GET_CODE (x) == HIGH)
- x = XEXP (x, 0);
-
/* Treat symbols as constants. Avoid TLS symbols as they are complex,
so spilling them is better than rematerialization. */
if (SYMBOL_REF_P (x) && !SYMBOL_REF_TLS_MODEL (x))
