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authorRichard Henderson <rth@redhat.com>2004-01-16 05:04:59 +0000
committerRichard Henderson <rth@redhat.com>2004-01-16 05:04:59 +0000
commit33f0a6c75ee574bd376da63c6e88de98989d3373 (patch)
tree4ee2ad96ff7a8064515089c1349c7e202d10d3b4
parent23e50ece453d94989cbb20c51c300f24386b08b2 (diff)
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* sysdeps/unix/sysv/linux/alpha/Makefile [stdlib]: Process ucontext-offsets.sym. * sysdeps/unix/sysv/linux/alpha/getcontext.S: New file. * sysdeps/unix/sysv/linux/alpha/makecontext.S: New file. * sysdeps/unix/sysv/linux/alpha/setcontext.S: New file. * sysdeps/unix/sysv/linux/alpha/swapcontext.S: New file. * sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym: New file.
* sysdeps/unix/sysv/linux/alpha/Makefile [stdlib]: Process ucontext-offsets.sym. * sysdeps/unix/sysv/linux/alpha/getcontext.S: New file. * sysdeps/unix/sysv/linux/alpha/makecontext.S: New file. * sysdeps/unix/sysv/linux/alpha/setcontext.S: New file. * sysdeps/unix/sysv/linux/alpha/swapcontext.S: New file. * sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym: New file. 2004-01-15 Richard Henderson <rth@redhat.com>
-rw-r--r--ChangeLog10
-rw-r--r--sysdeps/unix/sysv/linux/alpha/Makefile4
-rw-r--r--sysdeps/unix/sysv/linux/alpha/getcontext.S186
-rw-r--r--sysdeps/unix/sysv/linux/alpha/makecontext.S164
-rw-r--r--sysdeps/unix/sysv/linux/alpha/setcontext.S35
-rw-r--r--sysdeps/unix/sysv/linux/alpha/swapcontext.S51
-rw-r--r--sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym18
7 files changed, 468 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog
index 796b9be..5b1c1d1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
2004-01-15 Richard Henderson <rth@redhat.com>
+ * sysdeps/unix/sysv/linux/alpha/Makefile [stdlib]: Process
+ ucontext-offsets.sym.
+ * sysdeps/unix/sysv/linux/alpha/getcontext.S: New file.
+ * sysdeps/unix/sysv/linux/alpha/makecontext.S: New file.
+ * sysdeps/unix/sysv/linux/alpha/setcontext.S: New file.
+ * sysdeps/unix/sysv/linux/alpha/swapcontext.S: New file.
+ * sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym: New file.
+
+2004-01-15 Richard Henderson <rth@redhat.com>
+
* sysdeps/unix/sysv/linux/alpha/rt_sigaction.S: Prefix stubs with
__syscall_, move nop inside, adjust users by +4.
diff --git a/sysdeps/unix/sysv/linux/alpha/Makefile b/sysdeps/unix/sysv/linux/alpha/Makefile
index 3097cc3..37a9214 100644
--- a/sysdeps/unix/sysv/linux/alpha/Makefile
+++ b/sysdeps/unix/sysv/linux/alpha/Makefile
@@ -2,6 +2,10 @@ ifeq ($(subdir),posix)
sysdep_routines += oldglob
endif
+ifeq ($(subdir),stdlib)
+gen-as-const-headers += ucontext-offsets.sym
+endif
+
ifeq ($(subdir),misc)
sysdep_headers += alpha/ptrace.h alpha/regdef.h sys/io.h
diff --git a/sysdeps/unix/sysv/linux/alpha/getcontext.S b/sysdeps/unix/sysv/linux/alpha/getcontext.S
new file mode 100644
index 0000000..3566890
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/getcontext.S
@@ -0,0 +1,186 @@
+/* Save current context.
+ Copyright (C) 2004 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+#include <ucontext-offsets.h>
+
+/* ??? Should be a better place for this that's asm friendly. */
+#define SIG_BLOCK 1
+
+
+ENTRY (__getcontext)
+#ifdef PROF
+ ldgp gp, 0(pv)
+ .set noat
+ lda AT, _mcount
+ jsr AT, (AT), _mcount
+ .set at
+ .prologue 1
+#else
+ .prologue 0
+#endif
+
+ bsr $0, __getcontext_x
+ mov $31, $0
+ ret
+
+END(__getcontext)
+weak_alias(__getcontext, getcontext)
+
+
+/* An internal routine used by getcontext and setcontext.
+ The incomming return address register is $0. */
+
+ .align 4
+ .globl __getcontext_x
+ .hidden __getcontext_x
+ .usepv __getcontext_x, no
+
+ cfi_startproc
+ cfi_return_column (64)
+__getcontext_x:
+ cfi_register (64, 0)
+
+ /* Return value of getcontext. $0 is the only register
+ whose value is not preserved. */
+ stq $31, UC_SIGCTX+SC_REGS($16)
+
+ /* Store all registers into the context. */
+ stq $1, UC_SIGCTX+SC_REGS+1*8($16)
+ stq $2, UC_SIGCTX+SC_REGS+2*8($16)
+ stq $3, UC_SIGCTX+SC_REGS+3*8($16)
+ stq $4, UC_SIGCTX+SC_REGS+4*8($16)
+ stq $5, UC_SIGCTX+SC_REGS+5*8($16)
+ stq $6, UC_SIGCTX+SC_REGS+6*8($16)
+ stq $7, UC_SIGCTX+SC_REGS+7*8($16)
+ stq $8, UC_SIGCTX+SC_REGS+8*8($16)
+ stq $9, UC_SIGCTX+SC_REGS+9*8($16)
+ stq $10, UC_SIGCTX+SC_REGS+10*8($16)
+ stq $11, UC_SIGCTX+SC_REGS+11*8($16)
+ stq $12, UC_SIGCTX+SC_REGS+12*8($16)
+ stq $13, UC_SIGCTX+SC_REGS+13*8($16)
+ stq $14, UC_SIGCTX+SC_REGS+14*8($16)
+ stq $15, UC_SIGCTX+SC_REGS+15*8($16)
+ stq $16, UC_SIGCTX+SC_REGS+16*8($16)
+ stq $17, UC_SIGCTX+SC_REGS+17*8($16)
+ stq $18, UC_SIGCTX+SC_REGS+18*8($16)
+ stq $19, UC_SIGCTX+SC_REGS+19*8($16)
+ stq $20, UC_SIGCTX+SC_REGS+20*8($16)
+ stq $21, UC_SIGCTX+SC_REGS+21*8($16)
+ stq $22, UC_SIGCTX+SC_REGS+22*8($16)
+ stq $23, UC_SIGCTX+SC_REGS+23*8($16)
+ stq $24, UC_SIGCTX+SC_REGS+24*8($16)
+ stq $25, UC_SIGCTX+SC_REGS+25*8($16)
+ stq $26, UC_SIGCTX+SC_REGS+26*8($16)
+ stq $27, UC_SIGCTX+SC_REGS+27*8($16)
+ stq $28, UC_SIGCTX+SC_REGS+28*8($16)
+ stq $29, UC_SIGCTX+SC_REGS+29*8($16)
+ stq $30, UC_SIGCTX+SC_REGS+30*8($16)
+ stq $31, UC_SIGCTX+SC_REGS+31*8($16)
+
+ stt $f0, UC_SIGCTX+SC_FPREGS+0*8($16)
+ stt $f1, UC_SIGCTX+SC_FPREGS+1*8($16)
+ stt $f2, UC_SIGCTX+SC_FPREGS+2*8($16)
+ stt $f3, UC_SIGCTX+SC_FPREGS+3*8($16)
+ stt $f4, UC_SIGCTX+SC_FPREGS+4*8($16)
+ stt $f5, UC_SIGCTX+SC_FPREGS+5*8($16)
+ stt $f6, UC_SIGCTX+SC_FPREGS+6*8($16)
+ stt $f7, UC_SIGCTX+SC_FPREGS+7*8($16)
+ stt $f8, UC_SIGCTX+SC_FPREGS+8*8($16)
+ stt $f9, UC_SIGCTX+SC_FPREGS+9*8($16)
+ stt $f10, UC_SIGCTX+SC_FPREGS+10*8($16)
+ stt $f11, UC_SIGCTX+SC_FPREGS+11*8($16)
+ stt $f12, UC_SIGCTX+SC_FPREGS+12*8($16)
+ stt $f13, UC_SIGCTX+SC_FPREGS+13*8($16)
+ stt $f14, UC_SIGCTX+SC_FPREGS+14*8($16)
+ stt $f15, UC_SIGCTX+SC_FPREGS+15*8($16)
+ stt $f16, UC_SIGCTX+SC_FPREGS+16*8($16)
+ stt $f17, UC_SIGCTX+SC_FPREGS+17*8($16)
+ stt $f18, UC_SIGCTX+SC_FPREGS+18*8($16)
+ stt $f19, UC_SIGCTX+SC_FPREGS+19*8($16)
+ stt $f20, UC_SIGCTX+SC_FPREGS+20*8($16)
+ stt $f21, UC_SIGCTX+SC_FPREGS+21*8($16)
+ stt $f22, UC_SIGCTX+SC_FPREGS+22*8($16)
+ stt $f23, UC_SIGCTX+SC_FPREGS+23*8($16)
+ stt $f24, UC_SIGCTX+SC_FPREGS+24*8($16)
+ stt $f25, UC_SIGCTX+SC_FPREGS+25*8($16)
+ stt $f26, UC_SIGCTX+SC_FPREGS+26*8($16)
+ stt $f27, UC_SIGCTX+SC_FPREGS+27*8($16)
+ stt $f28, UC_SIGCTX+SC_FPREGS+28*8($16)
+ stt $f29, UC_SIGCTX+SC_FPREGS+29*8($16)
+ stt $f30, UC_SIGCTX+SC_FPREGS+30*8($16)
+ stt $f31, UC_SIGCTX+SC_FPREGS+31*8($16)
+
+ mf_fpcr $f0
+ lda $1, 8
+ stt $f0, UC_SIGCTX+SC_FPCR($16)
+
+ /* The return address of getcontext is the restart pc. */
+ stq $26, UC_SIGCTX+SC_PC($16)
+
+ /* Userlevel always has a processor status word of 8. */
+ stq $1, UC_SIGCTX+SC_PS($16)
+
+ /* Save registers around the syscall. We preserve $17
+ for the benefit of swapcontext. */
+ subq $30, 4*8, $30
+ cfi_adjust_cfa_offset(4*8)
+ stq $0, 0($30)
+ cfi_rel_offset(64, 0)
+ stq $16, 8($30)
+ stq $17, 16($30)
+
+ /* Save the current signal mask. Whee, there are three
+ copies of this in the alpha ucontext_t. */
+ lda $16, SIG_BLOCK
+ lda $17, 0
+ lda $0, __NR_osf_sigprocmask
+ callsys
+
+ ldq $16, 8($30)
+ ldq $17, 16($30)
+
+ stq $0, UC_OSF_SIGMASK($16)
+ stq $0, UC_SIGCTX+SC_MASK($16)
+ stq $0, UC_SIGMASK($16)
+ stq $31, UC_SIGMASK + 1*8($16)
+ stq $31, UC_SIGMASK + 2*8($16)
+ stq $31, UC_SIGMASK + 3*8($16)
+ stq $31, UC_SIGMASK + 4*8($16)
+ stq $31, UC_SIGMASK + 5*8($16)
+ stq $31, UC_SIGMASK + 6*8($16)
+ stq $31, UC_SIGMASK + 7*8($16)
+ stq $31, UC_SIGMASK + 8*8($16)
+ stq $31, UC_SIGMASK + 9*8($16)
+ stq $31, UC_SIGMASK +10*8($16)
+ stq $31, UC_SIGMASK +11*8($16)
+ stq $31, UC_SIGMASK +12*8($16)
+ stq $31, UC_SIGMASK +13*8($16)
+ stq $31, UC_SIGMASK +14*8($16)
+ stq $31, UC_SIGMASK +15*8($16)
+
+ ldq $0, 0($30)
+ addq $30, 4*8, $30
+ cfi_register (64, 0)
+ cfi_adjust_cfa_offset(-4*8)
+ ret $31, ($0), 1
+
+ cfi_endproc
+ .size __getcontext_x, .-__getcontext_x
+ .type __getcontext_x, @function
diff --git a/sysdeps/unix/sysv/linux/alpha/makecontext.S b/sysdeps/unix/sysv/linux/alpha/makecontext.S
new file mode 100644
index 0000000..223117e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/makecontext.S
@@ -0,0 +1,164 @@
+/* Copyright (C) 2004 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+#include <ucontext-offsets.h>
+
+
+ENTRY(__makecontext)
+ ldgp $29, 0($27)
+#ifdef PROF
+ .set noat
+ lda AT, _mcount
+ jsr AT, (AT), _mcount
+ .set at
+#endif
+ .prologue 1
+
+ /* Compute top of stack, including arguments. */
+ ldq $1, UC_STACK+SS_SP($16)
+ ldq $2, UC_STACK+SS_SIZE($16)
+ addq $1, $2, $8
+ subq $18, 6, $1
+ cmovlt $1, 0, $1
+ s8addq $1, 0, $2
+ subq $8, $2, $8
+
+ /* Copy all parameters. Switch statement header here. */
+ ldah $3, $jumptable($29) !gprelhigh
+ cmple $18, 6, $1
+ mov $18, $2
+ cmoveq $1, 7, $2
+ s4addq $2, $3, $3
+ ldl $4, $jumptable($3) !gprellow
+ addq $4, $29, $4
+ jmp $31, ($4), $args1
+
+ .section .rodata
+ .align 2
+$jumptable:
+ .gprel32 $args0
+ .gprel32 $args1
+ .gprel32 $args2
+ .gprel32 $args3
+ .gprel32 $args4
+ .gprel32 $args5
+ .gprel32 $args6
+ .gprel32 $argsN
+ .text
+
+ /* Here we process arguments 7 through N. This is a straight
+ stack-to-stack copy. */
+ .align 4
+$argsN:
+ subq $18, 6, $1
+ lda $2, 0($8)
+ lda $3, 3*8($30)
+ .align 4
+1:
+ ldq $0, 0($3)
+ subq $1, 1, $1
+ lda $3, 8($3)
+ stq $0, 0($2)
+ lda $2, 8($2)
+ bne $1, 1b
+
+ /* Here we process arguments 6 through 0. This involves
+ copying into the register save areas of the ucontext. */
+ .align 4
+$args6:
+ ldq $0, 2*8($30)
+ stq $0, UC_SIGCTX+SC_REGS+21*8($16)
+ unop
+ stq $0, UC_SIGCTX+SC_FPREGS+21*8($16)
+$args5:
+ ldq $0, 1*8($30)
+ stq $0, UC_SIGCTX+SC_REGS+20*8($16)
+ unop
+ stq $0, UC_SIGCTX+SC_FPREGS+20*8($16)
+$args4:
+ ldq $0, 0*8($30)
+ stq $0, UC_SIGCTX+SC_REGS+19*8($16)
+ unop
+ stq $0, UC_SIGCTX+SC_FPREGS+19*8($16)
+$args3:
+ unop
+ stq $21, UC_SIGCTX+SC_REGS+18*8($16)
+ unop
+ stt $f21, UC_SIGCTX+SC_FPREGS+18*8($16)
+$args2:
+ unop
+ stq $20, UC_SIGCTX+SC_REGS+17*8($16)
+ unop
+ stt $f20, UC_SIGCTX+SC_FPREGS+17*8($16)
+$args1:
+ unop
+ stq $19, UC_SIGCTX+SC_REGS+16*8($16)
+ unop
+ stt $f19, UC_SIGCTX+SC_FPREGS+16*8($16)
+$args0:
+
+ /* Set up the registers ready to invoke __startcontext.
+ We seed $27 with the target function address, and $9
+ with the link from ucp. */
+ ldah $0, __startcontext($29) !gprelhigh
+ ldq $1, UC_LINK($16)
+ lda $0, __startcontext($0) !gprellow
+ stq $17, UC_SIGCTX+SC_REGS+27*8($16)
+ stq $8, UC_SIGCTX+SC_REGS+30*8($16)
+ stq $0, UC_SIGCTX+SC_PC($16)
+ stq $1, UC_SIGCTX+SC_REGS+9*8($16)
+
+ /* No return value from makecontext. */
+ ret
+
+END(__makecontext)
+weak_alias (__makecontext, makecontext)
+
+/* This function is where a new makecontext "thread" begins life.
+ We have already set up $27 for calling the target function, and
+ we've set $9 to the UC_LINK of the parent context.
+
+ If the function returns, we either jump to the linked context
+ (if non-null) or exit. */
+
+ .align 4
+ .ent __startcontext
+__startcontext:
+ .frame $31, 0, $31, 0
+ .prologue 0
+
+ jsr $26, ($27), 0
+ ldgp $29, 0($26)
+ mov $9, $16
+ beq $9, 1f
+
+#ifdef PIC
+ bsr $26, __setcontext !samegp
+1: mov $31, $16
+ bsr $26, HIDDEN_JUMPTARGET(exit) !samegp
+#else
+ jsr $26, __setcontext
+ ldgp $29, 0($26)
+1: mov $31, $16
+ jsr $26, HIDDEN_JUMPTARGET(exit)
+#endif
+
+ halt
+
+ .end __startcontext
diff --git a/sysdeps/unix/sysv/linux/alpha/setcontext.S b/sysdeps/unix/sysv/linux/alpha/setcontext.S
new file mode 100644
index 0000000..7d443d4
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/setcontext.S
@@ -0,0 +1,35 @@
+/* Install given context.
+ Copyright (C) 2004 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+#include <ucontext-offsets.h>
+
+
+/* In case the user fiddled it, copy the "official" signal mask
+ from the ucontext_t into the sigcontext structure. */
+#undef PSEUDO_PREPARE_ARGS
+#define PSEUDO_PREPARE_ARGS \
+ ldq $0, UC_SIGMASK($16); \
+ stq $0, UC_SIGCTX+SC_MASK($16); \
+ lda $16, UC_SIGCTX($16);
+
+PSEUDO(__setcontext, sigreturn, 1)
+ ret
+PSEUDO_END(__setcontext)
+weak_alias(__setcontext, setcontext)
diff --git a/sysdeps/unix/sysv/linux/alpha/swapcontext.S b/sysdeps/unix/sysv/linux/alpha/swapcontext.S
new file mode 100644
index 0000000..5f6615e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/swapcontext.S
@@ -0,0 +1,51 @@
+/* Save current context and install the given one.
+ Copyright (C) 2004 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <sysdep.h>
+#include <ucontext-offsets.h>
+
+ENTRY(__swapcontext)
+
+#ifdef PROF
+ ldgp $29, 0($27)
+ .set noat
+ lda AT, _mcount
+ jsr AT, (AT), _mcount
+ .set at
+ .prologue 1
+#elif defined PIC
+ .prologue 0
+#else
+ ldgp $29, 0($27)
+ .prologue 1
+#endif
+
+#ifdef PIC
+ unop
+ bsr $0, __getcontext_x !samegp
+ mov $17, $16
+ br $31, __setcontext !samegp
+#else
+ jsr $0, __getcontext_x
+ mov $17, $16
+ jmp $31, __setcontext
+#endif
+
+END(__swapcontext)
+weak_alias(__swapcontext, swapcontext)
diff --git a/sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym b/sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym
new file mode 100644
index 0000000..f95ff75
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/ucontext-offsets.sym
@@ -0,0 +1,18 @@
+#include <stddef.h>
+#include <sys/ucontext.h>
+
+--
+UC_LINK offsetof (ucontext_t, uc_link)
+UC_OSF_SIGMASK offsetof (ucontext_t, __uc_osf_sigmask)
+UC_STACK offsetof (ucontext_t, uc_stack)
+UC_SIGCTX offsetof (ucontext_t, uc_mcontext)
+UC_SIGMASK offsetof (ucontext_t, uc_sigmask)
+SC_REGS offsetof (struct sigcontext, sc_regs)
+SC_FPREGS offsetof (struct sigcontext, sc_fpregs)
+SC_PC offsetof (struct sigcontext, sc_pc)
+SC_PS offsetof (struct sigcontext, sc_ps)
+SC_FPCRS offsetof (struct sigcontext, sc_fpcr)
+SC_MASK offsetof (struct sigcontext, sc_mask)
+SC_FPCR offsetof (struct sigcontext, sc_fpcr)
+SS_SP offsetof (stack_t, ss_sp)
+SS_SIZE offsetof (stack_t, ss_size)