build: avoid build failure on some HPPA systems

* src/longlong.h: Restrict some HPPA assembly variants to PA RISC V2.0.
Note we also avoid this assembly for ilp32 runtimes, since even though
the assembly is accepted there, it's not safe as the context can get
clobbered between the 'add' and 'add,dc'.
This fixes a compile failure with newer HPPA systems with default
GCC CPU options.
Reported by John David Anglin

diff --git a/src/longlong.h b/src/longlong.h
index 8d7161113ef427d88c37270fa55aebd6a6f393c7..6ee157cda8e8927beab5e9599caaf320facff77d 100644 (file)
--- a/src/longlong.h
+++ b/src/longlong.h
@@ -679,7 +679,13 @@ extern UWtype __MPN(udiv_qrnnd) (UWtype *, UWtype, UWtype, UWtype);
 /* These macros are for ABI=2.0w.  In ABI=2.0n they can't be used, since GCC
    (3.2) puts longlong into two adjacent 32-bit registers.  Presumably this
    is just a case of no direct support for 2.0n but treating it like 1.0. */
-#if defined (__hppa) && W_TYPE_SIZE == 64 && ! defined (_LONG_LONG_LIMB)
+#if defined (__hppa) && W_TYPE_SIZE == 64 && ! defined (_LONG_LONG_LIMB) \
+  && defined (_PA_RISC2_0) && defined (_LP64)
+/* Note the _PA_RISC2_0 above is to exclude this code from GCC with
+   default -march options which doesn't support these instructions.
+   Also the width check for 'long' is to avoid ilp32 runtimes where
+   GNU/Linux and narrow HP-UX kernels are known to have issues with
+   clobbering of context between the add and add,dc instructions.  */
 #define add_ssaaaa(sh, sl, ah, al, bh, bl) \
   __asm__ ("add%I5 %5,%r4,%1\n\tadd,dc %r2,%r3,%0"                     \
           : "=r" (sh), "=&r" (sl)                                      \