From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailserv2.iuinc.com (IDENT:qmailr@mailserv2.iuinc.com [206.245.164.55]) by puffin.external.hp.com (8.9.3/8.9.3) with SMTP id OAA09576 for ; Thu, 22 Jun 2000 14:30:45 -0600 To: Alan Modra Cc: parisc-linux@thepuffingroup.com Subject: Re: [parisc-linux] Get rid of %r8 linker stubs In-Reply-To: Your message of "Thu, 22 Jun 2000 00:07:14 +1000." References: Date: Thu, 22 Jun 2000 14:33:09 -0600 From: Paul Bame Message-Id: List-ID: = = Hello all, = The attached patch to puffin.external.hp.com CVS binutils-2.10 = implements a new linker stub scheme for elf32-hppa. (Well, it's new for = gnu - I believe the hp linker does something like this). = = The new scheme works like this: For any linker input section that needs a = stub to reach called routines, the linker creates a stub section located = immediately prior to the input section. A call is simply redirected to = the stub, which consists of a long branch = ldil LR'XXX,%r1 = be,n RR'XXX(%sr4,%r1) = to the destination. = = The old scheme had a single stub section, and out-of-range calls changed = the call instruction from "b,l faraway,%r2" to "be,l stub(%sr4,%r8)". = This of course dedicates a register to point to the stubs, and has some = serious problems caused by changing the return pointer from the normal %r2 = to the implicit %r31 used by "be,l". Additionally, when we finally = implement elf32-hppa shared libraries, there are going to be a _lot_ more = stubs. We may even exceed the maximum 256k of stubs, especially if we try = to combine .plt and .got with stubs to get a register back. = = Anyway, I'd appreciate some brave souls testing out this patch. A few = positive reports and I'll check the lot in to pehc. Well the good news is I can (with some trouble) link a native binutils. The bad news is that the kernel won't link. To wit - hppa1.1-linux-ld: fs/fs.o: cannot reach stub 080e89b4_00000000_printk hppa1.1-linux-ld: fs/fs.o: cannot handle relocation R_PARISC_PCREL17F for printk at 0x3fc98 in .text This follows a 'make clean'. I only re-built the new binutils and not gcc, if that matters. -P