Clean up the arm64 setjmp.

Note that this doesn't address the fact that we don't save/restore the
real-time signals. But it does let us pass the tests we currently fail.

Bug: 16918359
Change-Id: I063a6926164289a71026a412da7f5dd2ca9a74b3

5 files changed, 144 insertions, 297 deletions

diff --git a/libc/arch-arm64/arm64.mk b/libc/arch-arm64/arm64.mk
index bb6ca63..ba78871 100644
--- a/libc/arch-arm64/arm64.mk
+++ b/libc/arch-arm64/arm64.mk
@@ -35,10 +35,8 @@ libc_openbsd_src_files_arm64 += \
 libc_bionic_src_files_arm64 += \
     arch-arm64/bionic/__bionic_clone.S \
     arch-arm64/bionic/_exit_with_stack_teardown.S \
-    arch-arm64/bionic/_setjmp.S \
     arch-arm64/bionic/setjmp.S \
     arch-arm64/bionic/__set_tls.c \
-    arch-arm64/bionic/sigsetjmp.S \
     arch-arm64/bionic/syscall.S \
     arch-arm64/bionic/vfork.S \
 
diff --git a/libc/arch-arm64/bionic/_setjmp.S b/libc/arch-arm64/bionic/_setjmp.S
deleted file mode 100644
index e11ef68..0000000
--- a/libc/arch-arm64/bionic/_setjmp.S
+++ /dev/null
@@ -1,111 +0,0 @@
-/*
- * Copyright (C) 2013 The Android Open Source Project
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *  * Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- *  * Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <private/bionic_asm.h>
-#include <machine/setjmp.h>
-
-/*
- * C library - _setjmp, _longjmp
- *
- * _longjmp(jmp_buf state, int value)
- * will generate a "return(v)" from the last call to _setjmp(state) by restoring
- * registers from the stack. The previous signal state is NOT restored.
- *
- * NOTE: x0 return value
- *       x9-x15 temporary registers
- */
-
-ENTRY(_setjmp)
-    /* store magic number */
-    ldr     w9, .L_setjmp_magic
-    str     w9, [x0, #(_JB_MAGIC * 4)]
-
-    /* store core registers */
-    mov     x10, sp
-    stp     x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
-    stp     x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
-    stp     x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
-    stp     x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
-    stp     x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
-    stp     x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
-    str     x19,      [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
-
-    /* store floating point registers */
-    stp     d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
-    stp     d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
-    stp     d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
-    stp     d8,  d9,  [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
-
-    mov     w0, wzr
-    ret
-END(_setjmp)
-
-.L_setjmp_magic:
-    .word   _JB_MAGIC__SETJMP
-
-ENTRY(_longjmp)
-    /* check magic */
-    ldr     w9, .L_setjmp_magic
-    ldr     w10, [x0, #(_JB_MAGIC * 4)]
-    cmp     w9, w10
-    b.ne    .L_fail
-
-    /* restore core registers */
-    ldp     x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
-    mov     sp, x10
-    ldp     x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
-    ldp     x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
-    ldp     x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
-    ldp     x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
-    ldp     x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
-    ldr     x19,      [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
-
-    /* restore floating point registers */
-    ldp     d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
-    ldp     d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
-    ldp     d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
-    ldp     d8,  d9,  [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
-
-    /* validate sp (sp mod 16 = 0) and lr (lr mod 4 = 0) */
-    tst     x30, #3
-    b.ne    .L_fail
-    mov     x10, sp
-    tst     x10, #15
-    b.ne    .L_fail
-
-    /* set return value */
-    cmp     w1, wzr
-    csinc   w0, w1, wzr, ne
-    ret
-
-    /* validation failed, die die die */
-.L_fail:
-    bl      longjmperror
-    bl      abort
-    b        . - 8       /* Cannot get here */
-END(_longjmp)
diff --git a/libc/arch-arm64/bionic/setjmp.S b/libc/arch-arm64/bionic/setjmp.S
index 35815a6..8aeb95a 100644
--- a/libc/arch-arm64/bionic/setjmp.S
+++ b/libc/arch-arm64/bionic/setjmp.S
@@ -27,97 +27,151 @@
  */
 
 #include <private/bionic_asm.h>
-#include <machine/setjmp.h>
 
-/*
- * C library - _setjmp, _longjmp
- *
- * _longjmp(jmp_buf state, int value)
- * will generate a "return(v)" from the last call to _setjmp(state) by restoring
- * registers from the stack. The previous signal state is NOT restored.
- *
- * NOTE: x0 return value
- *       x9-x15 temporary registers
- */
+// _JBLEN is the size of a jmp_buf in longs(64bit on AArch64).
+#define _JBLEN 32
+
+// According to AARCH64 PCS document we need to save the following
+// registers:
+//
+// Core     x19 - x30, sp (see section 5.1.1)
+// VFP      d8 - d15 (see section 5.1.2)
+//
+// NOTE: All the registers saved here will have 64bit vales (except FPSR).
+//       AAPCS mandates that the higher part of q registers do not need to
+//       be saved by the callee.
+//
+
+// The structure of jmp_buf for AArch64:
+//
+// NOTE: _JBLEN is the size of jmp_buf in longs(64bit on AArch64)! The table
+//      below computes the offsets in words(32bit).
+//
+//  word        name            description
+//  0       magic           magic number
+//  1       sigmask         signal mask (not used with _setjmp / _longjmp)
+//  2       core_base       base of core registers (x19-x30, sp)
+//  28      float_base      base of float registers (d8-d15)
+//  44      reserved        reserved entries (room to grow)
+//  64
+//
+//
+//  NOTE: The instructions that load/store core/vfp registers expect 8-byte
+//        alignment. Contrary to the previous setjmp header for ARM we do not
+//        need to save status/control registers for VFP (it is not a
+//        requirement for setjmp).
+//
+
+#define _JB_MAGIC       0
+#define _JB_SIGMASK     (_JB_MAGIC+1)
+#define _JB_CORE_BASE   (_JB_SIGMASK+1)
+#define _JB_FLOAT_BASE  (_JB_CORE_BASE + (31-19+1)*2)
+
+.L_setjmp_magic_signal_mask_n: .word 0x53657200
+.L_setjmp_magic_signal_mask_y: .word 0x53657201
 
 ENTRY(setjmp)
-    /* block all signals an retrieve signal mask */
-    stp     x0, x30, [sp, #-16]!
-
-    mov     x0, xzr
-    bl      sigblock
-    mov     w1, w0
-
-    ldp     x0, x30, [sp], #16
-
-    /* store signal mask */
-    str     w1, [x0, #(_JB_SIGMASK *4)]
-
-    /* store magic number */
-    ldr     w9, .L_setjmp_magic
-    str     w9, [x0, #(_JB_MAGIC * 4)]
-
-    /* store core registers */
-    mov     x10, sp
-    stp     x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
-    stp     x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
-    stp     x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
-    stp     x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
-    stp     x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
-    stp     x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
-    str     x19,      [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
-
-    /* store floating point registers */
-    stp     d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
-    stp     d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
-    stp     d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
-    stp     d8,  d9,  [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
-
-    mov     w0, wzr
-    ret
+  mov w1, #1
+  b sigsetjmp
 END(setjmp)
 
-.L_setjmp_magic:
-    .word   _JB_MAGIC__SETJMP
-
-ENTRY(longjmp)
-    /* check magic */
-    ldr     w9, .L_setjmp_magic
-    ldr     w10, [x0, #(_JB_MAGIC * 4)]
-    cmp     w9, w10
-    b.ne    .L_fail
-
-    /* restore core registers */
-    ldp     x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
-    mov     sp, x10
-    ldp     x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
-    ldp     x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
-    ldp     x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
-    ldp     x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
-    ldp     x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
-    ldr     x19,      [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
-
-    /* restore floating point registers */
-    ldp     d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
-    ldp     d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
-    ldp     d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
-    ldp     d8,  d9,  [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
-
-    /* validate sp (sp mod 16 = 0) and lr (lr mod 4 = 0) */
-    tst     x30, #3
-    b.ne    .L_fail
-    mov     x10, sp
-    tst     x10, #15
-    b.ne    .L_fail
-
-    /* set return value */
-    cmp     w1, wzr
-    csinc   w0, w1, wzr, ne
-    ret
-
-    /* validation failed, die die die */
-.L_fail:
-    bl      longjmperror
-    bl      abort
-    b       . - 8       /* Cannot get here */
-END(longjmp)
+ENTRY(_setjmp)
+  mov w1, #0
+  b sigsetjmp
+END(_setjmp)
+
+// int sigsetjmp(sigjmp_buf env, int save_signal_mask);
+ENTRY(sigsetjmp)
+  // Do we need to save the signal mask?
+  ldr w9, .L_setjmp_magic_signal_mask_n
+  cbz w1, 1f
+
+  // Get current signal mask.
+  stp x0, x30, [sp, #-16]!
+  mov x0, xzr
+  bl sigblock
+  mov w1, w0
+  ldp x0, x30, [sp], #16
+
+  // Save signal mask.
+  str w1, [x0, #(_JB_SIGMASK * 4)]
+
+  ldr w9, .L_setjmp_magic_signal_mask_y
+
+1:
+  // Save magic number.
+  str w9, [x0, #(_JB_MAGIC * 4)]
+
+  // Save core registers.
+  mov x10, sp
+  stp x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
+  stp x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
+  stp x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
+  stp x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
+  stp x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
+  stp x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
+  str x19,      [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
+
+  // Save floating point registers.
+  stp d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
+  stp d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
+  stp d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
+  stp d8,  d9,  [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
+
+  mov w0, wzr
+  ret
+END(sigsetjmp)
+
+// void siglongjmp(sigjmp_buf env, int value);
+ENTRY(siglongjmp)
+  // Check magic.
+  ldr w10, [x0, #(_JB_MAGIC * 4)]
+  ldr w9, .L_setjmp_magic_signal_mask_n
+  cmp w9, w10
+  b.eq 1f
+  ldr w9, .L_setjmp_magic_signal_mask_y
+  cmp w9, w10
+  b.ne longjmperror
+
+  // Restore signal mask.
+  stp x0, x30, [sp, #-16]!
+  mov x19, x1
+  ldr w0, [x0, #(_JB_SIGMASK * 4)]
+  bl sigsetmask
+  ldp x0, x30, [sp], #16
+  mov x1, x19
+
+1:
+  // Restore core registers.
+  ldp x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
+  mov sp, x10
+  ldp x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
+  ldp x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
+  ldp x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
+  ldp x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
+  ldp x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
+  ldr x19,      [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
+
+  // Restore floating point registers.
+  ldp d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
+  ldp d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
+  ldp d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
+  ldp d8,  d9,  [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
+
+  // Validate sp (sp mod 16 = 0) and lr (lr mod 4 = 0).
+  tst x30, #3
+  b.ne longjmperror
+  mov x10, sp
+  tst x10, #15
+  b.ne longjmperror
+
+  // Set return value.
+  cmp w1, wzr
+  csinc w0, w1, wzr, ne
+  ret
+END(siglongjmp)
+
+  .globl longjmp
+  .equ longjmp, siglongjmp
+  .globl _longjmp
+  .equ _longjmp, siglongjmp
diff --git a/libc/arch-arm64/bionic/sigsetjmp.S b/libc/arch-arm64/bionic/sigsetjmp.S
deleted file mode 100644
index be7cecb..0000000
--- a/libc/arch-arm64/bionic/sigsetjmp.S
+++ /dev/null
@@ -1,51 +0,0 @@
-/*
- * Copyright (C) 2013 The Android Open Source Project
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *  * Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- *  * Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <private/bionic_asm.h>
-#include <machine/setjmp.h>
-
-/*
- * int sigsetjmp(sigjmp_buf env, int savesigs);
- * void siglongjmp(sigjmp_buf env, int val);
- */
-
-ENTRY(sigsetjmp)
-    cbz     w1, _setjmp
-    b       setjmp
-END(sigsetjmp)
-
-.L_setjmp_magic:
-    .word   _JB_MAGIC__SETJMP
-
-ENTRY(siglongjmp)
-    ldr     w2, .L_setjmp_magic
-    ldr     w3, [x0]
-    cmp     w2, w3
-    b.eq    _longjmp
-    b       longjmp
-END(siglongjmp)
diff --git a/libc/arch-arm64/include/machine/setjmp.h b/libc/arch-arm64/include/machine/setjmp.h
index 1c237da..27c2fe5 100644
--- a/libc/arch-arm64/include/machine/setjmp.h
+++ b/libc/arch-arm64/include/machine/setjmp.h
@@ -26,48 +26,5 @@
  * SUCH DAMAGE.
  */
 
-/*
- * machine/setjmp.h: machine dependent setjmp-related information.
- */
-
-/* _JBLEN is the size of a jmp_buf in longs(64bit on AArch64) */
+/* _JBLEN is the size of a jmp_buf in longs (64bit on AArch64) */
 #define _JBLEN 32
-
-/* According to AARCH64 PCS document we need to save the following
- * registers:
- *
- * Core     x19 - x30, sp (see section 5.1.1)
- * VFP      d8 - d15 (see section 5.1.2)
- *
- * NOTE: All the registers saved here will have 64bit vales (except FPSR).
- *       AAPCS mandates that the higher part of q registers does not need to
- *       be saveved by the callee.
- */
-
-/* The structure of jmp_buf for AArch64:
- *
- * NOTE: _JBLEN is the size of jmp_buf in longs(64bit on AArch64)! The table
- *      below computes the offsets in words(32bit).
- *
- *  word        name            description
- *  0       magic           magic number
- *  1       sigmask         signal mask (not used with _setjmp / _longjmp)
- *  2       core_base       base of core registers (x19-x30, sp)
- *  28      float_base      base of float registers (d8-d15)
- *  44      reserved        reserved entries (room to grow)
- *  64
- *
- *
- *  NOTE: The instructions that load/store core/vfp registers expect 8-byte
- *        alignment. Contrary to the previous setjmp header for ARM we do not
- *        need to save status/control registers for VFP (it is not a
- *        requirement for setjmp).
- */
-
-#define _JB_MAGIC       0
-#define _JB_SIGMASK     (_JB_MAGIC+1)
-#define _JB_CORE_BASE   (_JB_SIGMASK+1)
-#define _JB_FLOAT_BASE  (_JB_CORE_BASE + (31-19+1)*2)
-
-#define _JB_MAGIC__SETJMP   0x53657200
-#define _JB_MAGIC_SETJMP    0x53657201