Fix setting inline hint based on InstanceDef::requires_inline

For instances where `InstanceDef::requires_inline` is true, an attempt
is made to set an inline hint though a call to the `inline` function.
The attempt is ineffective, since all attributes will be usually removed
by the second call.

Fix the issue by applying the attributes only once, with user provided
attributes having a priority when provided.
This commit is contained in:
Tomasz Miąsko 2020-11-17 00:00:00 +00:00
parent f5230fbf76
commit 4ea25da237
2 changed files with 35 additions and 12 deletions

View File

@ -25,7 +25,7 @@ use crate::value::Value;
/// Mark LLVM function to use provided inline heuristic. /// Mark LLVM function to use provided inline heuristic.
#[inline] #[inline]
fn inline(cx: &CodegenCx<'ll, '_>, val: &'ll Value, inline: InlineAttr) { fn inline(cx: &CodegenCx<'ll, '_>, val: &'ll Value, inline: InlineAttr, requires_inline: bool) {
use self::InlineAttr::*; use self::InlineAttr::*;
match inline { match inline {
Hint => Attribute::InlineHint.apply_llfn(Function, val), Hint => Attribute::InlineHint.apply_llfn(Function, val),
@ -35,11 +35,8 @@ fn inline(cx: &CodegenCx<'ll, '_>, val: &'ll Value, inline: InlineAttr) {
Attribute::NoInline.apply_llfn(Function, val); Attribute::NoInline.apply_llfn(Function, val);
} }
} }
None => { None if requires_inline => Attribute::InlineHint.apply_llfn(Function, val),
Attribute::InlineHint.unapply_llfn(Function, val); None => {}
Attribute::AlwaysInline.unapply_llfn(Function, val);
Attribute::NoInline.unapply_llfn(Function, val);
}
}; };
} }
@ -229,12 +226,7 @@ pub fn from_fn_attrs(cx: &CodegenCx<'ll, 'tcx>, llfn: &'ll Value, instance: ty::
} }
} }
// FIXME(eddyb) consolidate these two `inline` calls (and avoid overwrites). inline(cx, llfn, codegen_fn_attrs.inline.clone(), instance.def.requires_inline(cx.tcx));
if instance.def.requires_inline(cx.tcx) {
inline(cx, llfn, attributes::InlineAttr::Hint);
}
inline(cx, llfn, codegen_fn_attrs.inline.clone());
// The `uwtable` attribute according to LLVM is: // The `uwtable` attribute according to LLVM is:
// //

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@ -0,0 +1,31 @@
// Checks that closures, constructors, and shims except
// for a drop glue receive inline hint by default.
//
// compile-flags: -Cno-prepopulate-passes -Zsymbol-mangling-version=v0
#![crate_type = "lib"]
pub fn f() {
let a = A;
let b = (0i32, 1i32, 2i32, 3i32);
let c = || {};
a(String::new(), String::new());
b.clone();
c();
}
struct A(String, String);
// CHECK: ; core::ptr::drop_in_place::<inline_hint::A>
// CHECK-NEXT: ; Function Attrs:
// CHECK-NOT: inlinehint
// CHECK-SAME: {{$}}
// CHECK: ; <(i32, i32, i32, i32) as core::clone::Clone>::clone
// CHECK-NEXT: ; Function Attrs: inlinehint
// CHECK: ; inline_hint::f::{closure#0}
// CHECK-NEXT: ; Function Attrs: inlinehint
// CHECK: ; inline_hint::A
// CHECK-NEXT: ; Function Attrs: inlinehint