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1; RUN: llc < %s -mtriple=x86_64-pc-windows-msvc | FileCheck %s
2; Control Flow Guard is currently only available on Windows
3
4declare dllimport i32 @target_func1()
5declare dllimport i32 @target_func2()
6declare dllimport i32 @target_func3()
7@ptrs = dso_local local_unnamed_addr global [2 x void ()*] [void ()* bitcast (i32 ()* @target_func2 to void ()*), void ()* bitcast (i32 ()* @target_func3 to void ()*)], align 16
8
9; Test address-taken functions from imported DLLs are correctly added to the
10; Guard Address-Taken IAT Entry (.giats) and Guard Function ID (.gfids) sections.
11define i32 @func_cf_giats1() {
12entry:
13  ; Since it is a dllimport, target_func1 will be represented as "__imp_target_func1" when it is
14  ; stored in the function pointer. Therefore, the .giats section must contain "__imp_target_func1".
15  ; Unlike MSVC, we also have "target_func1" in the .gfids section, since this is not a security risk.
16  %func_ptr = alloca i32 ()*, align 8
17  store i32 ()* @target_func1, i32 ()** %func_ptr, align 8
18  %0 = load i32 ()*, i32 ()** %func_ptr, align 8
19  %1 = call i32 %0()
20  ; target_func2 is called directly from a global array, so should only appear in the .gfids section.
21  %2 = load i32 ()*, i32 ()** bitcast ([2 x void ()*]* @ptrs to i32 ()**), align 8
22  %3 = call i32 %2()
23  ; target_func3 is called both via a stored function pointer (as with target_func1) and via a gloabl
24  ; array (as with target_func2), so "target_func3" must appear in .gfids and "__imp_target_func3" in .giats.
25  store i32 ()* @target_func3, i32 ()** %func_ptr, align 8
26  %4 = load i32 ()*, i32 ()** %func_ptr, align 8
27  %5 = call i32 %4()
28  %6 = load i32 ()*, i32 ()** bitcast (void ()** getelementptr inbounds ([2 x void ()*], [2 x void ()*]* @ptrs, i64 0, i64 1) to i32 ()**), align 8
29  %7 = call i32 %6()
30  ret i32 %5
31}
32
33; CHECK-LABEL: .section .gfids$y,"dr"
34; CHECK-NEXT:  .symidx target_func1
35; CHECK-NEXT:  .symidx target_func2
36; CHECK-NEXT:  .symidx target_func3
37; CHECK-NOT:   .symidx
38; CHECK-LABEL: .section .giats$y,"dr"
39; CHECK-NEXT:  .symidx __imp_target_func1
40; CHECK-NEXT:  .symidx __imp_target_func3
41; CHECK-NOT:   .symidx
42
43!llvm.module.flags = !{!0}
44!0 = !{i32 2, !"cfguard", i32 2}
45