Merge pull request #196 from madsmtm/deduplicate-common-selectors

Deduplicate common selectors

Author: madsmtm

Cargo.toml

@@ -13,3 +13,8 @@ members = [
     "test-ui",
 ]
 resolver = "2"
+
+[profile.assembly-tests]
+inherits = "release"
+# Enable LTO to allow testing the `unstable-static-sel-inlined` feature
+lto = true

objc2/src/__macro_helpers.rs

@@ -1,3 +1,4 @@
+use crate::__sel_inner;
 use crate::rc::{Allocated, Id, Ownership};
 use crate::runtime::{Class, Sel};
 use crate::{Message, MessageArguments, MessageReceiver};
@@ -12,6 +13,31 @@ pub use core::{compile_error, concat, panic, stringify};
 #[cfg(feature = "objc2-proc-macros")]
 pub use objc2_proc_macros::__hash_idents;
 
+// Common selectors.
+//
+// These are put here to deduplicate the cached selector, and when using
+// `unstable-static-sel`, the statics.
+//
+// Note that our assembly tests of `unstable-static-sel-inlined` output a GOT
+// entry for such accesses, but that is just a limitation of our tests - the
+// actual assembly is as one would expect.
+
+#[inline]
+pub fn alloc() -> Sel {
+    // SAFETY: Must have NUL byte
+    __sel_inner!("alloc\0", uniqueIdent)
+}
+#[inline]
+pub fn init() -> Sel {
+    // SAFETY: Must have NUL byte
+    __sel_inner!("init\0", uniqueIdent)
+}
+#[inline]
+pub fn new() -> Sel {
+    // SAFETY: Must have NUL byte
+    __sel_inner!("new\0", uniqueIdent)
+}
+
 /// Helper for specifying the retain semantics for a given selector family.
 ///
 /// Note that we can't actually check if a method is in a method family; only

objc2/src/macros.rs

@@ -45,8 +45,11 @@ macro_rules! class {
 /// # Specification
 ///
 /// This has similar syntax and functionality as the `@selector` directive in
-/// Objective-C. This calls [`Sel::register`] internally. The result is cached
-/// for efficiency.
+/// Objective-C.
+///
+/// This calls [`Sel::register`] internally. The result is cached for
+/// efficiency. The cache for certain common selectors (`alloc`, `init` and
+/// `new`) is deduplicated to reduce code-size.
 ///
 /// Non-ascii identifiers are ill-tested, if supported at all.
 ///
@@ -142,6 +145,15 @@ macro_rules! class {
 /// ```
 #[macro_export]
 macro_rules! sel {
+    (alloc) => ({
+        $crate::__macro_helpers::alloc()
+    });
+    (init) => ({
+        $crate::__macro_helpers::init()
+    });
+    (new) => ({
+        $crate::__macro_helpers::new()
+    });
     ($first:ident $(: $($rest:ident :)*)?) => ({
         use $crate::__macro_helpers::{concat, stringify, str};
         const SELECTOR_DATA: &str = concat!(stringify!($first), $(':', $(stringify!($rest), ':',)*)? '\0');
@@ -153,7 +165,7 @@ macro_rules! sel {
 #[macro_export]
 #[cfg(not(feature = "unstable-static-sel"))]
 macro_rules! __sel_inner {
-    ($data:ident, $($idents:ident)+) => {{
+    ($data:expr, $($idents:ident)+) => {{
         use $crate::__macro_helpers::CachedSel;
         static CACHED_SEL: CachedSel = CachedSel::new();
         #[allow(unused_unsafe)]
@@ -170,10 +182,10 @@ macro_rules! __sel_inner_statics_apple_generic {
         $image_info_section:literal;
         $var_name_section:literal;
         $selector_ref_section:literal;
-        $data:ident,
+        $data:expr,
         $($idents:ident)+
     } => {
-        use $crate::__macro_helpers::{__hash_idents, u8, UnsafeCell};
+        use $crate::__macro_helpers::{u8, UnsafeCell};
         use $crate::ffi::__ImageInfo;
         use $crate::runtime::Sel;
 
@@ -185,7 +197,10 @@ macro_rules! __sel_inner_statics_apple_generic {
         /// reports `__DATA/__objc_imageinfo has unexpectedly large size XXX`,
         /// but things still seems to work.
         #[link_section = $image_info_section]
-        #[export_name = concat!("\x01L_OBJC_IMAGE_INFO_", __hash_idents!($($idents)+))]
+        #[export_name = $crate::__macro_helpers::concat!(
+            "\x01L_OBJC_IMAGE_INFO_",
+            $crate::__macro_helpers::__hash_idents!($($idents)+),
+        )]
         #[used] // Make sure this reaches the linker
         static _IMAGE_INFO: __ImageInfo = __ImageInfo::system();
 
@@ -195,7 +210,10 @@ macro_rules! __sel_inner_statics_apple_generic {
         /// See rust-lang/rust#18297
         /// Should only be an optimization (?)
         #[link_section = $var_name_section]
-        #[export_name = concat!("\x01L_OBJC_METH_VAR_NAME_", __hash_idents!($($idents)+))]
+        #[export_name = $crate::__macro_helpers::concat!(
+            "\x01L_OBJC_METH_VAR_NAME_",
+            $crate::__macro_helpers::__hash_idents!($($idents)+),
+        )]
         static NAME_DATA: [u8; X.len()] = {
             // Convert the `&[u8]` slice to an array with known length, so
             // that we can place that directly in a static.
@@ -236,7 +254,10 @@ macro_rules! __sel_inner_statics_apple_generic {
         /// See the [`ctor`](https://crates.io/crates/ctor) crate for more
         /// info on "life before main".
         #[link_section = $selector_ref_section]
-        #[export_name = concat!("\x01L_OBJC_SELECTOR_REFERENCES_", __hash_idents!($($idents)+))]
+        #[export_name = $crate::__macro_helpers::concat!(
+            "\x01L_OBJC_SELECTOR_REFERENCES_",
+            $crate::__macro_helpers::__hash_idents!($($idents)+),
+        )]
         static mut REF: UnsafeCell<Sel> = unsafe {
             UnsafeCell::new(Sel::__internal_from_ptr(NAME_DATA.as_ptr().cast()))
         };

test-assembly/crates/test_msg_send_static_sel/expected/apple-aarch64.s

@@ -16,21 +16,24 @@ _handle_alloc_init:
 	stp	x29, x30, [sp, #16]
 	add	x29, sp, #16
 Lloh2:
-	adrp	x8, L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328@PAGE
+	adrp	x8, L_OBJC_SELECTOR_REFERENCES_0ea0a15a3d108c32@GOTPAGE
 Lloh3:
-	ldr	x19, [x8, L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328@PAGEOFF]
+	ldr	x8, [x8, L_OBJC_SELECTOR_REFERENCES_0ea0a15a3d108c32@GOTPAGEOFF]
 Lloh4:
-	adrp	x8, L_OBJC_SELECTOR_REFERENCES_dcb825748735621d@PAGE
+	ldr	x19, [x8]
 Lloh5:
-	ldr	x1, [x8, L_OBJC_SELECTOR_REFERENCES_dcb825748735621d@PAGEOFF]
+	adrp	x8, L_OBJC_SELECTOR_REFERENCES_1678d2f7468155d2@GOTPAGE
+Lloh6:
+	ldr	x8, [x8, L_OBJC_SELECTOR_REFERENCES_1678d2f7468155d2@GOTPAGEOFF]
+Lloh7:
+	ldr	x1, [x8]
 	bl	_objc_msgSend
 	mov	x1, x19
 	ldp	x29, x30, [sp, #16]
 	ldp	x20, x19, [sp], #32
 	b	_objc_msgSend
-	.loh AdrpLdr	Lloh4, Lloh5
-	.loh AdrpAdrp	Lloh2, Lloh4
-	.loh AdrpLdr	Lloh2, Lloh3
+	.loh AdrpLdrGotLdr	Lloh5, Lloh6, Lloh7
+	.loh AdrpLdrGotLdr	Lloh2, Lloh3, Lloh4
 
 	.globl	_use_generic
 	.p2align	2
@@ -39,32 +42,32 @@ _use_generic:
 	stp	x29, x30, [sp, #16]
 	add	x29, sp, #16
 	mov	x19, x0
-Lloh6:
+Lloh8:
 	adrp	x8, L_OBJC_SELECTOR_REFERENCES_f16064a6f68ca673@PAGE
-Lloh7:
+Lloh9:
 	ldr	x1, [x8, L_OBJC_SELECTOR_REFERENCES_f16064a6f68ca673@PAGEOFF]
 	adrp	x20, L_OBJC_SELECTOR_REFERENCES_457d234345d46cbe@PAGE
 	ldr	x2, [x20, L_OBJC_SELECTOR_REFERENCES_457d234345d46cbe@PAGEOFF]
 	bl	_objc_msgSend
-Lloh8:
+Lloh10:
 	adrp	x8, L_OBJC_SELECTOR_REFERENCES_9f134b97cb598446@PAGE
-Lloh9:
+Lloh11:
 	ldr	x1, [x8, L_OBJC_SELECTOR_REFERENCES_9f134b97cb598446@PAGEOFF]
 	ldr	x2, [x20, L_OBJC_SELECTOR_REFERENCES_457d234345d46cbe@PAGEOFF]
 	mov	x0, x19
 	bl	_objc_msgSend
-Lloh10:
+Lloh12:
 	adrp	x8, L_OBJC_SELECTOR_REFERENCES_e76e01e8b2327e5d@PAGE
-Lloh11:
+Lloh13:
 	ldr	x1, [x8, L_OBJC_SELECTOR_REFERENCES_e76e01e8b2327e5d@PAGEOFF]
 	ldr	x2, [x20, L_OBJC_SELECTOR_REFERENCES_457d234345d46cbe@PAGEOFF]
 	mov	x0, x19
 	ldp	x29, x30, [sp, #16]
 	ldp	x20, x19, [sp], #32
 	b	_objc_msgSend
+	.loh AdrpLdr	Lloh12, Lloh13
 	.loh AdrpLdr	Lloh10, Lloh11
 	.loh AdrpLdr	Lloh8, Lloh9
-	.loh AdrpLdr	Lloh6, Lloh7
 
 	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
 	.globl	L_OBJC_IMAGE_INFO_044375a4329d08dc
@@ -83,40 +86,6 @@ L_OBJC_METH_VAR_NAME_044375a4329d08dc:
 L_OBJC_SELECTOR_REFERENCES_044375a4329d08dc:
 	.quad	L_OBJC_METH_VAR_NAME_044375a4329d08dc
 
-	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
-	.globl	L_OBJC_IMAGE_INFO_cb49b9ab1b00e328
-	.p2align	2
-L_OBJC_IMAGE_INFO_cb49b9ab1b00e328:
-	.asciz	"\000\000\000\000@\000\000"
-
-	.section	__TEXT,__objc_methname,cstring_literals
-	.globl	L_OBJC_METH_VAR_NAME_cb49b9ab1b00e328
-L_OBJC_METH_VAR_NAME_cb49b9ab1b00e328:
-	.asciz	"init"
-
-	.section	__DATA,__objc_selrefs,literal_pointers,no_dead_strip
-	.globl	L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328
-	.p2align	3
-L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328:
-	.quad	L_OBJC_METH_VAR_NAME_cb49b9ab1b00e328
-
-	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
-	.globl	L_OBJC_IMAGE_INFO_dcb825748735621d
-	.p2align	2
-L_OBJC_IMAGE_INFO_dcb825748735621d:
-	.asciz	"\000\000\000\000@\000\000"
-
-	.section	__TEXT,__objc_methname,cstring_literals
-	.globl	L_OBJC_METH_VAR_NAME_dcb825748735621d
-L_OBJC_METH_VAR_NAME_dcb825748735621d:
-	.asciz	"alloc"
-
-	.section	__DATA,__objc_selrefs,literal_pointers,no_dead_strip
-	.globl	L_OBJC_SELECTOR_REFERENCES_dcb825748735621d
-	.p2align	3
-L_OBJC_SELECTOR_REFERENCES_dcb825748735621d:
-	.quad	L_OBJC_METH_VAR_NAME_dcb825748735621d
-
 	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
 	.globl	L_OBJC_IMAGE_INFO_457d234345d46cbe
 	.p2align	2

test-assembly/crates/test_msg_send_static_sel/expected/apple-armv7.s

@@ -16,14 +16,16 @@ LPC0_0:
 _handle_alloc_init:
 	push	{r4, r7, lr}
 	add	r7, sp, #4
-	movw	r1, :lower16:(L_OBJC_SELECTOR_REFERENCES_dcb825748735621d-(LPC1_0+8))
-	movt	r1, :upper16:(L_OBJC_SELECTOR_REFERENCES_dcb825748735621d-(LPC1_0+8))
+	movw	r1, :lower16:(LL_OBJC_SELECTOR_REFERENCES_0ea0a15a3d108c32$non_lazy_ptr-(LPC1_0+8))
+	movt	r1, :upper16:(LL_OBJC_SELECTOR_REFERENCES_0ea0a15a3d108c32$non_lazy_ptr-(LPC1_0+8))
+	movw	r2, :lower16:(LL_OBJC_SELECTOR_REFERENCES_1678d2f7468155d2$non_lazy_ptr-(LPC1_1+8))
+	movt	r2, :upper16:(LL_OBJC_SELECTOR_REFERENCES_1678d2f7468155d2$non_lazy_ptr-(LPC1_1+8))
 LPC1_0:
 	ldr	r1, [pc, r1]
-	movw	r4, :lower16:(L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328-(LPC1_1+8))
-	movt	r4, :upper16:(L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328-(LPC1_1+8))
 LPC1_1:
-	ldr	r4, [pc, r4]
+	ldr	r2, [pc, r2]
+	ldr	r4, [r1]
+	ldr	r1, [r2]
 	bl	_objc_msgSend
 	mov	r1, r4
 	pop	{r4, r7, lr}
@@ -84,40 +86,6 @@ L_OBJC_METH_VAR_NAME_044375a4329d08dc:
 L_OBJC_SELECTOR_REFERENCES_044375a4329d08dc:
 	.long	L_OBJC_METH_VAR_NAME_044375a4329d08dc
 
-	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
-	.globl	L_OBJC_IMAGE_INFO_cb49b9ab1b00e328
-	.p2align	2
-L_OBJC_IMAGE_INFO_cb49b9ab1b00e328:
-	.asciz	"\000\000\000\000@\000\000"
-
-	.section	__TEXT,__objc_methname,cstring_literals
-	.globl	L_OBJC_METH_VAR_NAME_cb49b9ab1b00e328
-L_OBJC_METH_VAR_NAME_cb49b9ab1b00e328:
-	.asciz	"init"
-
-	.section	__DATA,__objc_selrefs,literal_pointers,no_dead_strip
-	.globl	L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328
-	.p2align	2
-L_OBJC_SELECTOR_REFERENCES_cb49b9ab1b00e328:
-	.long	L_OBJC_METH_VAR_NAME_cb49b9ab1b00e328
-
-	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
-	.globl	L_OBJC_IMAGE_INFO_dcb825748735621d
-	.p2align	2
-L_OBJC_IMAGE_INFO_dcb825748735621d:
-	.asciz	"\000\000\000\000@\000\000"
-
-	.section	__TEXT,__objc_methname,cstring_literals
-	.globl	L_OBJC_METH_VAR_NAME_dcb825748735621d
-L_OBJC_METH_VAR_NAME_dcb825748735621d:
-	.asciz	"alloc"
-
-	.section	__DATA,__objc_selrefs,literal_pointers,no_dead_strip
-	.globl	L_OBJC_SELECTOR_REFERENCES_dcb825748735621d
-	.p2align	2
-L_OBJC_SELECTOR_REFERENCES_dcb825748735621d:
-	.long	L_OBJC_METH_VAR_NAME_dcb825748735621d
-
 	.section	__DATA,__objc_imageinfo,regular,no_dead_strip
 	.globl	L_OBJC_IMAGE_INFO_457d234345d46cbe
 	.p2align	2
@@ -186,4 +154,13 @@ L_OBJC_METH_VAR_NAME_e76e01e8b2327e5d:
 L_OBJC_SELECTOR_REFERENCES_e76e01e8b2327e5d:
 	.long	L_OBJC_METH_VAR_NAME_e76e01e8b2327e5d
 
+	.section	__DATA,__nl_symbol_ptr,non_lazy_symbol_pointers
+	.p2align	2
+LL_OBJC_SELECTOR_REFERENCES_0ea0a15a3d108c32$non_lazy_ptr:
+	.indirect_symbol	L_OBJC_SELECTOR_REFERENCES_0ea0a15a3d108c32
+	.long	0
+LL_OBJC_SELECTOR_REFERENCES_1678d2f7468155d2$non_lazy_ptr:
+	.indirect_symbol	L_OBJC_SELECTOR_REFERENCES_1678d2f7468155d2
+	.long	0
+
 .subsections_via_symbols