previously, only archs that needed to do stack cleanup defined a
__cp_cancel label for acting on cancellation in their syscall asm, and
a default definition was provided by a weak alias to __cancel, the C
function. this resulted in wrong codegen for arm on gcc versions
affected by pr 68178 and possibly similar issues (like pr 66609) on
other archs, and also created an inconsistency where the __cp_begin
and __cp_end labels were treated as const data but __cp_cancel was
treated as a function. this in turn caused incorrect code generation
on archs where function pointers point to function descriptors rather
than code (for now, only sh/fdpic).
__syscall_cp_asm:
__cp_begin:
ldr w0,[x0]
__syscall_cp_asm:
__cp_begin:
ldr w0,[x0]
mov x8,x1
mov x0,x2
mov x1,x3
mov x8,x1
mov x0,x2
mov x1,x3
-
- // cbnz might not be able to jump far enough
-1: b __cancel
+__cp_cancel:
+ b __cancel
__syscall_cp_asm:
__cp_begin:
lwi r5, r5, 0
__syscall_cp_asm:
__cp_begin:
lwi r5, r5, 0
addi r12, r6, 0
add r5, r7, r0
add r6, r8, r0
addi r12, r6, 0
add r5, r7, r0
add r6, r8, r0
__cp_end:
rtsd r15, 8
nop
__cp_end:
rtsd r15, 8
nop
+__cp_cancel:
+ bri __cancel
__cp_begin:
l.lwz r3, 0(r3)
l.sfeqi r3, 0
__cp_begin:
l.lwz r3, 0(r3)
l.sfeqi r3, 0
l.ori r11, r4, 0
l.ori r3, r5, 0
l.ori r4, r6, 0
l.ori r11, r4, 0
l.ori r3, r5, 0
l.ori r4, r6, 0
+__cp_cancel:
+ l.j __cancel
+ l.nop
cmpwi cr7, 0, 0 #compare r0 with 0, store result in cr7.
beq+ cr7, 1f #jump to label 1 if r0 was 0
cmpwi cr7, 0, 0 #compare r0 with 0, store result in cr7.
beq+ cr7, 1f #jump to label 1 if r0 was 0
- b __cancel #else call cancel
+ b __cp_cancel #else call cancel
1:
#ok, the cancel flag was not set
# syscall: number goes to r0, the rest 3-8
1:
#ok, the cancel flag was not set
# syscall: number goes to r0, the rest 3-8
#else negate result.
neg 3, 3
blr
#else negate result.
neg 3, 3
blr
+__cp_cancel:
+ b __cancel
#ifdef SHARED
__attribute__((__visibility__("hidden")))
#endif
#ifdef SHARED
__attribute__((__visibility__("hidden")))
#endif
-long __cancel(), __cp_cancel(), __syscall_cp_asm(), __syscall_cp_c();
+long __cancel(), __syscall_cp_asm(), __syscall_cp_c();
-/* If __syscall_cp_asm has adjusted the stack pointer, it must provide a
- * definition of __cp_cancel to undo those adjustments and call __cancel.
- * Otherwise, __cancel provides a definition for __cp_cancel. */
-
-weak_alias(__cancel, __cp_cancel);
-
long __syscall_cp_asm(volatile void *, syscall_arg_t,
syscall_arg_t, syscall_arg_t, syscall_arg_t,
syscall_arg_t, syscall_arg_t, syscall_arg_t);
long __syscall_cp_asm(volatile void *, syscall_arg_t,
syscall_arg_t, syscall_arg_t, syscall_arg_t,
syscall_arg_t, syscall_arg_t, syscall_arg_t);
#ifdef SHARED
__attribute__((__visibility__("hidden")))
#endif
#ifdef SHARED
__attribute__((__visibility__("hidden")))
#endif
-extern const char __cp_begin[1], __cp_end[1];
+extern const char __cp_begin[1], __cp_end[1], __cp_cancel[1];
static void cancel_handler(int sig, siginfo_t *si, void *ctx)
{
static void cancel_handler(int sig, siginfo_t *si, void *ctx)
{
__cp_begin:
mov.l @r4, r4
tst r4, r4
__cp_begin:
mov.l @r4, r4
tst r4, r4
- bt 2f
-
- mov.l L1, r0
- braf r0
- nop
-1:
-
-.align 2
-L1: .long __cancel@PLT-(1b-.)
-
-2: mov r5, r3
+ bf __cp_cancel
+ mov r5, r3
mov r6, r4
mov r7, r5
mov.l @r15, r6
mov r6, r4
mov r7, r5
mov.l @r15, r6
+
+__cp_cancel:
+ mov.l 2f, r0
+ braf r0
+ nop
+1:
+
+.align 2
+2: .long __cancel@PCREL-(1b-.)
__cp_begin:
mov (%rdi),%eax
test %eax,%eax
__cp_begin:
mov (%rdi),%eax
test %eax,%eax
mov %rdi,%r11
mov %rsi,%rax
mov %rdx,%rdi
mov %rdi,%r11
mov %rsi,%rax
mov %rdx,%rdi
+__cp_cancel:
+ jmp __cancel
__cp_begin:
mov (%rdi),%eax
test %eax,%eax
__cp_begin:
mov (%rdi),%eax
test %eax,%eax
mov %rdi,%r11
mov %rsi,%rax
mov %rdx,%rdi
mov %rdi,%r11
mov %rsi,%rax
mov %rdx,%rdi
+__cp_cancel:
+ jmp __cancel