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-rw-r--r--compiler/rustc_codegen_gcc/src/builder.rs2
-rw-r--r--compiler/rustc_codegen_llvm/src/builder.rs17
-rw-r--r--compiler/rustc_codegen_llvm/src/llvm/ffi.rs2
-rw-r--r--compiler/rustc_codegen_llvm/src/llvm_util.rs6
-rw-r--r--compiler/rustc_codegen_ssa/src/mir/block.rs10
-rw-r--r--compiler/rustc_codegen_ssa/src/traits/builder.rs2
-rw-r--r--compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp8
-rw-r--r--src/test/codegen/unwind-landingpad-cold.rs15
-rw-r--r--src/test/codegen/unwind-landingpad-inline.rs37
9 files changed, 12 insertions, 87 deletions
diff --git a/compiler/rustc_codegen_gcc/src/builder.rs b/compiler/rustc_codegen_gcc/src/builder.rs
index b430dc329cb..974e59b65ec 100644
--- a/compiler/rustc_codegen_gcc/src/builder.rs
+++ b/compiler/rustc_codegen_gcc/src/builder.rs
@@ -1403,7 +1403,7 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
         self.cx
     }
 
-    fn apply_attrs_to_cleanup_callsite(&mut self, _llret: RValue<'gcc>) {
+    fn do_not_inline(&mut self, _llret: RValue<'gcc>) {
         unimplemented!();
     }
 
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index 5e78d6fc851..3703e902bb7 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -23,7 +23,6 @@ use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::Span;
 use rustc_target::abi::{self, call::FnAbi, Align, Size, WrappingRange};
 use rustc_target::spec::{HasTargetSpec, Target};
-use smallvec::SmallVec;
 use std::borrow::Cow;
 use std::ffi::CStr;
 use std::iter;
@@ -1175,19 +1174,9 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         unsafe { llvm::LLVMBuildZExt(self.llbuilder, val, dest_ty, UNNAMED) }
     }
 
-    fn apply_attrs_to_cleanup_callsite(&mut self, llret: &'ll Value) {
-        let mut attrs = SmallVec::<[_; 2]>::new();
-
-        // Cleanup is always the cold path.
-        attrs.push(llvm::AttributeKind::Cold.create_attr(self.llcx));
-
-        // In LLVM versions with deferred inlining (currently, system LLVM < 14),
-        // inlining drop glue can lead to exponential size blowup, see #41696 and #92110.
-        if !llvm_util::is_rust_llvm() && llvm_util::get_version() < (14, 0, 0) {
-            attrs.push(llvm::AttributeKind::NoInline.create_attr(self.llcx));
-        }
-
-        attributes::apply_to_callsite(llret, llvm::AttributePlace::Function, &attrs);
+    fn do_not_inline(&mut self, llret: &'ll Value) {
+        let noinline = llvm::AttributeKind::NoInline.create_attr(self.llcx);
+        attributes::apply_to_callsite(llret, llvm::AttributePlace::Function, &[noinline]);
     }
 }
 
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 31d1460e178..93eddb7359f 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -1932,8 +1932,6 @@ extern "C" {
     pub fn LLVMRustVersionMinor() -> u32;
     pub fn LLVMRustVersionPatch() -> u32;
 
-    pub fn LLVMRustIsRustLLVM() -> bool;
-
     /// Add LLVM module flags.
     ///
     /// In order for Rust-C LTO to work, module flags must be compatible with Clang. What
diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs
index b1c14c7e44b..6c974eb9c0b 100644
--- a/compiler/rustc_codegen_llvm/src/llvm_util.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs
@@ -257,12 +257,6 @@ pub fn get_version() -> (u32, u32, u32) {
     }
 }
 
-/// Returns `true` if this LLVM is Rust's bundled LLVM (and not system LLVM).
-pub fn is_rust_llvm() -> bool {
-    // Can be called without initializing LLVM
-    unsafe { llvm::LLVMRustIsRustLLVM() }
-}
-
 pub fn print_passes() {
     // Can be called without initializing LLVM
     unsafe {
diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
index f6c41af41b4..a87daa8d6b8 100644
--- a/compiler/rustc_codegen_ssa/src/mir/block.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -166,7 +166,7 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
                 bx.invoke(fn_ty, fn_ptr, &llargs, ret_llbb, unwind_block, self.funclet(fx));
             bx.apply_attrs_callsite(&fn_abi, invokeret);
             if fx.mir[self.bb].is_cleanup {
-                bx.apply_attrs_to_cleanup_callsite(invokeret);
+                bx.do_not_inline(invokeret);
             }
 
             if let Some((ret_dest, target)) = destination {
@@ -178,7 +178,11 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
             let llret = bx.call(fn_ty, fn_ptr, &llargs, self.funclet(fx));
             bx.apply_attrs_callsite(&fn_abi, llret);
             if fx.mir[self.bb].is_cleanup {
-                bx.apply_attrs_to_cleanup_callsite(llret);
+                // Cleanup is always the cold path. Don't inline
+                // drop glue. Also, when there is a deeply-nested
+                // struct, there are "symmetry" issues that cause
+                // exponential inlining - see issue #41696.
+                bx.do_not_inline(llret);
             }
 
             if let Some((ret_dest, target)) = destination {
@@ -1444,7 +1448,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
             let llret = bx.call(fn_ty, fn_ptr, &[], None);
             bx.apply_attrs_callsite(&fn_abi, llret);
-            bx.apply_attrs_to_cleanup_callsite(llret);
+            bx.do_not_inline(llret);
 
             bx.unreachable();
 
diff --git a/compiler/rustc_codegen_ssa/src/traits/builder.rs b/compiler/rustc_codegen_ssa/src/traits/builder.rs
index 1c7fe060ea4..37f2bfd3c4f 100644
--- a/compiler/rustc_codegen_ssa/src/traits/builder.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/builder.rs
@@ -479,5 +479,5 @@ pub trait BuilderMethods<'a, 'tcx>:
     ) -> Self::Value;
     fn zext(&mut self, val: Self::Value, dest_ty: Self::Type) -> Self::Value;
 
-    fn apply_attrs_to_cleanup_callsite(&mut self, llret: Self::Value);
+    fn do_not_inline(&mut self, llret: Self::Value);
 }
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index d627af48ba5..be3c1b02a05 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -694,14 +694,6 @@ extern "C" uint32_t LLVMRustVersionMinor() { return LLVM_VERSION_MINOR; }
 
 extern "C" uint32_t LLVMRustVersionMajor() { return LLVM_VERSION_MAJOR; }
 
-extern "C" bool LLVMRustIsRustLLVM() {
-#ifdef LLVM_RUSTLLVM
-  return true;
-#else
-  return false;
-#endif
-}
-
 extern "C" void LLVMRustAddModuleFlag(
     LLVMModuleRef M,
     Module::ModFlagBehavior MergeBehavior,
diff --git a/src/test/codegen/unwind-landingpad-cold.rs b/src/test/codegen/unwind-landingpad-cold.rs
deleted file mode 100644
index aa00b793654..00000000000
--- a/src/test/codegen/unwind-landingpad-cold.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-// no-system-llvm: needs #92110
-// compile-flags: -Cno-prepopulate-passes
-#![crate_type = "lib"]
-
-// This test checks that drop calls in unwind landing pads
-// get the `cold` attribute.
-
-// CHECK-LABEL: @check_cold
-// CHECK: {{(call|invoke) void .+}}drop_in_place{{.+}} [[ATTRIBUTES:#[0-9]+]]
-// CHECK: attributes [[ATTRIBUTES]] = { cold }
-#[no_mangle]
-pub fn check_cold(f: fn(), x: Box<u32>) {
-    // this may unwind
-    f();
-}
diff --git a/src/test/codegen/unwind-landingpad-inline.rs b/src/test/codegen/unwind-landingpad-inline.rs
deleted file mode 100644
index ce78d075dd0..00000000000
--- a/src/test/codegen/unwind-landingpad-inline.rs
+++ /dev/null
@@ -1,37 +0,0 @@
-// no-system-llvm: needs #92110 + patch for Rust alloc/dealloc functions
-// compile-flags: -Copt-level=3
-#![crate_type = "lib"]
-
-// This test checks that we can inline drop_in_place in
-// unwind landing pads.
-
-// Without inlining, the box pointers escape via the call to drop_in_place,
-// and LLVM will not optimize out the pointer comparison.
-// With inlining, everything should be optimized out.
-// See https://github.com/rust-lang/rust/issues/46515
-// CHECK-LABEL: @check_no_escape_in_landingpad
-// CHECK: start:
-// CHECK-NEXT: ret void
-#[no_mangle]
-pub fn check_no_escape_in_landingpad(f: fn()) {
-    let x = &*Box::new(0);
-    let y = &*Box::new(0);
-
-    if x as *const _ == y as *const _ {
-        f();
-    }
-}
-
-// Without inlining, the compiler can't tell that
-// dropping an empty string (in a landing pad) does nothing.
-// With inlining, the landing pad should be optimized out.
-// See https://github.com/rust-lang/rust/issues/87055
-// CHECK-LABEL: @check_eliminate_noop_drop
-// CHECK: start:
-// CHECK-NEXT: call void %g()
-// CHECK-NEXT: ret void
-#[no_mangle]
-pub fn check_eliminate_noop_drop(g: fn()) {
-    let _var = String::new();
-    g();
-}
generated by cgit-pink 1.4.1-3-g733a5 (git 2.37.1) at 2026-01-13 21:50:02 +0000