mirror of
https://github.com/apple/swift.git
synced 2025-12-14 20:36:38 +01:00
Merge pull request #85222 from mikeash/client-retain-release-no-weak-defs
[Runtime] Avoid weak definitions for client retain/release.
This commit is contained in:
Mike Ash
GitHub
@@ -36,6 +36,11 @@
|
||||
// offset so that it's still correct when the weak reference resolves to zero.
|
||||
.weak_reference __swift_retainRelease_slowpath_mask_v1
|
||||
|
||||
// preservemost retain/release entrypoints in the runtime
|
||||
.weak_reference _swift_retain_preservemost
|
||||
.weak_reference _swift_release_preservemost
|
||||
|
||||
|
||||
// Grab our own copy of the slowpath mask. This mask is a value which indicates
|
||||
// when we must call into the runtime slowpath. If the object's refcount field
|
||||
// has any bits set that are in the mask, then we must take the slow path. The
|
||||
@@ -87,57 +92,13 @@ ret
|
||||
// limits, in addition to the usual x19 and up. Any calls to functions that use
|
||||
// the standard calling convention need to save/restore x9-x15.
|
||||
|
||||
.globl _swift_retain_preservemost
|
||||
.weak_definition _swift_retain_preservemost
|
||||
_swift_retain_preservemost:
|
||||
maybe_pacibsp
|
||||
stp x0, x9, [sp, #-0x50]!
|
||||
stp x10, x11, [sp, #0x10]
|
||||
stp x12, x13, [sp, #0x20]
|
||||
stp x14, x15, [sp, #0x30]
|
||||
stp fp, lr, [sp, #0x40];
|
||||
add fp, sp, #0x40
|
||||
|
||||
// Clear the unused bits from the pointer
|
||||
and x0, x0, #BRIDGEOBJECT_POINTER_BITS
|
||||
bl _swift_retain
|
||||
|
||||
ldp fp, lr, [sp, #0x40]
|
||||
ldp x14, x15, [sp, #0x30]
|
||||
ldp x12, x13, [sp, #0x20]
|
||||
ldp x10, x11, [sp, #0x10]
|
||||
ldp x0, x9, [sp], #0x50
|
||||
ret_maybe_ab
|
||||
|
||||
.globl _swift_release_preservemost
|
||||
.weak_definition _swift_release_preservemost
|
||||
_swift_release_preservemost:
|
||||
maybe_pacibsp
|
||||
str x9, [sp, #-0x50]!
|
||||
stp x10, x11, [sp, #0x10]
|
||||
stp x12, x13, [sp, #0x20]
|
||||
stp x14, x15, [sp, #0x30]
|
||||
stp fp, lr, [sp, #0x40];
|
||||
add fp, sp, #0x40
|
||||
|
||||
// Clear the unused bits from the pointer
|
||||
and x0, x0, #BRIDGEOBJECT_POINTER_BITS
|
||||
bl _swift_release
|
||||
|
||||
ldp fp, lr, [sp, #0x40]
|
||||
ldp x14, x15, [sp, #0x30]
|
||||
ldp x12, x13, [sp, #0x20]
|
||||
ldp x10, x11, [sp, #0x10]
|
||||
ldr x9, [sp], #0x50
|
||||
ret_maybe_ab
|
||||
|
||||
.private_extern _swift_bridgeObjectReleaseClient
|
||||
#if SWIFT_OBJC_INTEROP
|
||||
_swift_bridgeObjectReleaseClient:
|
||||
tbz x0, #63, LbridgeObjectReleaseNotTagged
|
||||
ret
|
||||
LbridgeObjectReleaseNotTagged:
|
||||
tbnz x0, #62, _bridgeObjectReleaseClientObjC
|
||||
tbnz x0, #62, LbridgeObjectReleaseClientObjC
|
||||
and x0, x0, 0x0ffffffffffffff8
|
||||
|
||||
#else
|
||||
@@ -221,10 +182,35 @@ Lrelease_ret:
|
||||
Lslowpath_release:
|
||||
CONDITIONAL USE_LDX_STX, \
|
||||
clrex
|
||||
// If the weak preservemost symbol is NULL, call our helper. Otherwise call the
|
||||
// runtime directly.
|
||||
adrp x17, _swift_release_preservemost@GOTPAGE
|
||||
ldr x17, [x17, _swift_release_preservemost@GOTPAGEOFF]
|
||||
cbz x17, Lcall_swift_release
|
||||
b _swift_release_preservemost
|
||||
|
||||
.alt_entry _bridgeObjectReleaseClientObjC
|
||||
_bridgeObjectReleaseClientObjC:
|
||||
// Save/restore the preservemost registers and call swift_retain.
|
||||
Lcall_swift_release:
|
||||
maybe_pacibsp
|
||||
str x9, [sp, #-0x50]!
|
||||
stp x10, x11, [sp, #0x10]
|
||||
stp x12, x13, [sp, #0x20]
|
||||
stp x14, x15, [sp, #0x30]
|
||||
stp fp, lr, [sp, #0x40];
|
||||
add fp, sp, #0x40
|
||||
|
||||
// Clear the unused bits from the pointer
|
||||
and x0, x0, #BRIDGEOBJECT_POINTER_BITS
|
||||
bl _swift_release
|
||||
|
||||
ldp fp, lr, [sp, #0x40]
|
||||
ldp x14, x15, [sp, #0x30]
|
||||
ldp x12, x13, [sp, #0x20]
|
||||
ldp x10, x11, [sp, #0x10]
|
||||
ldr x9, [sp], #0x50
|
||||
ret_maybe_ab
|
||||
|
||||
LbridgeObjectReleaseClientObjC:
|
||||
maybe_pacibsp
|
||||
stp x0, x9, [sp, #-0x50]!
|
||||
stp x10, x11, [sp, #0x10]
|
||||
@@ -252,7 +238,7 @@ _swift_bridgeObjectRetainClient:
|
||||
tbz x0, #63, LbridgeObjectRetainNotTagged
|
||||
ret
|
||||
LbridgeObjectRetainNotTagged:
|
||||
tbnz x0, #62, _swift_bridgeObjectRetainClientObjC
|
||||
tbnz x0, #62, Lswift_bridgeObjectRetainClientObjC
|
||||
|
||||
.alt_entry _swift_retainClient
|
||||
#else
|
||||
@@ -334,10 +320,35 @@ Lretain_ret:
|
||||
Lslowpath_retain:
|
||||
CONDITIONAL USE_LDX_STX, \
|
||||
clrex
|
||||
// If the weak preservemost symbol is NULL, call our helper. Otherwise call the
|
||||
// runtime directly.
|
||||
adrp x17, _swift_retain_preservemost@GOTPAGE
|
||||
ldr x17, [x17, _swift_retain_preservemost@GOTPAGEOFF]
|
||||
cbz x17, Lcall_swift_retain
|
||||
b _swift_retain_preservemost
|
||||
|
||||
.alt_entry _swift_bridgeObjectRetainClientObjC
|
||||
_swift_bridgeObjectRetainClientObjC:
|
||||
// Save/restore the preservemost registers and call swift_retain.
|
||||
Lcall_swift_retain:
|
||||
maybe_pacibsp
|
||||
stp x0, x9, [sp, #-0x50]!
|
||||
stp x10, x11, [sp, #0x10]
|
||||
stp x12, x13, [sp, #0x20]
|
||||
stp x14, x15, [sp, #0x30]
|
||||
stp fp, lr, [sp, #0x40];
|
||||
add fp, sp, #0x40
|
||||
|
||||
// Clear the unused bits from the pointer
|
||||
and x0, x0, #BRIDGEOBJECT_POINTER_BITS
|
||||
bl _swift_retain
|
||||
|
||||
ldp fp, lr, [sp, #0x40]
|
||||
ldp x14, x15, [sp, #0x30]
|
||||
ldp x12, x13, [sp, #0x20]
|
||||
ldp x10, x11, [sp, #0x10]
|
||||
ldp x0, x9, [sp], #0x50
|
||||
ret_maybe_ab
|
||||
|
||||
Lswift_bridgeObjectRetainClientObjC:
|
||||
maybe_pacibsp
|
||||
stp x0, x9, [sp, #-0x50]!
|
||||
stp x10, x11, [sp, #0x10]
|
||||
|
||||
@@ -1147,5 +1147,4 @@ Added: __swift_debug_metadataAllocatorPageSize
|
||||
// New symbols to support emit-into-client retain/release.
|
||||
Added: __swift_retainRelease_slowpath_mask_v1
|
||||
Added: _swift_release_preservemost
|
||||
Added: _swift_release_preservemost_weak_placeholder
|
||||
Added: _swift_retain_preservemost
|
||||
|
||||
@@ -1,20 +1,19 @@
|
||||
// Ensure that we do not export any unwanted weak symbols from the dylibs.
|
||||
// Ensure that we do not export any weak symbols from the dylibs.
|
||||
//
|
||||
// Weak symbols require additional work from the loader to resolve the symbol at
|
||||
// load time and can cause ODR violations as well as unexpected symbol
|
||||
// satisfaction because the weak symbol may be used from a separate module.
|
||||
//
|
||||
// The _swift_release_preservemost_weak_placeholder symbol is present to allow
|
||||
// strong symbols from swiftCore to override weak symbols in other libraries,
|
||||
// to allow back-deployment usage of the swift_retain_preservemost and
|
||||
// swift_release_preservemost entrypoints.
|
||||
// Weak symbols in the runtime also conflict with the use of weak symbols in
|
||||
// embedded Swift. The presence of any weak symbol in swiftCore will allow its
|
||||
// strong symbols to override the weak symbols in the embedded runtime, and they
|
||||
// are not compatible.
|
||||
|
||||
// RUN: %empty-directory(%t)
|
||||
|
||||
// RUN: %llvm-nm --defined-only --extern-only --demangle %platform-dylib-dir/%target-library-name(swiftCore) > %t/swiftCore-all.txt
|
||||
// RUN: %llvm-nm --defined-only --extern-only --no-weak --demangle %platform-dylib-dir/%target-library-name(swiftCore) > %t/swiftCore-no-weak.txt
|
||||
// RUN: grep -v _swift_release_preservemost_weak_placeholder < %t/swiftCore-all.txt > %t/swiftCore-all-filtered.txt
|
||||
// RUN: diff -u %t/swiftCore-all-filtered.txt %t/swiftCore-no-weak.txt
|
||||
// RUN: diff -u %t/swiftCore-all.txt %t/swiftCore-no-weak.txt
|
||||
|
||||
// RUN: %llvm-nm --defined-only --extern-only --demangle %platform-dylib-dir/%target-library-name(swiftRemoteMirror) > %t/swiftRemoteMirror-all.txt
|
||||
// RUN: %llvm-nm --defined-only --extern-only --no-weak --demangle %platform-dylib-dir/%target-library-name(swiftRemoteMirror) > %t/swiftRemoteMirror-no-weak.txt
|
||||
|
||||
Reference in New Issue
Block a user