c866762272
This attribute is used to prevent tail-call optimizations to the marked
function. For example, in the following piece of code, foo1 will not be
tail-call optimized:
int __attribute__((not_tail_called)) foo1(int);
int foo2(int a) {
return foo1(a); // Tail-call optimization is not performed.
}
The attribute has effect only on statically bound calls. It has no
effect on indirect calls. Also, virtual functions and objective-c
methods cannot be marked as 'not_tail_called'.
rdar://problem/22667622
Differential Revision: http://reviews.llvm.org/D12922
llvm-svn: 252369
18 lines
442 B
C++
18 lines
442 B
C++
// RUN: %clang_cc1 -triple=x86_64-apple-darwin -std=c++11 -emit-llvm -o - %s | FileCheck %s
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class Class1 {
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public:
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[[clang::not_tail_called]] int m1();
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int m2();
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};
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int foo1(int a, Class1 *c1) {
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if (a)
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return c1->m1();
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return c1->m2();
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}
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// CHECK-LABEL: define i32 @_Z4foo1iP6Class1(
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// CHECK: %{{[a-z0-9]+}} = notail call i32 @_ZN6Class12m1Ev(%class.Class1*
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// CHECK: %{{[a-z0-9]+}} = call i32 @_ZN6Class12m2Ev(%class.Class1*
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