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1; RUN: llc < %s -mtriple=i686-win32 | FileCheck %s
2; RUN: llc < %s -mtriple=i686-win32 -O0 | FileCheck %s
3
4; IR simplified from the following C++ snippet compiled for i686-windows-msvc:
5
6; struct A { A(); ~A(); int a; };
7;
8; struct B {
9;   virtual int  f(int);
10;   virtual int  g(A, int, A);
11;   virtual void h(A, int, A);
12;   virtual A    i(A, int, A);
13;   virtual A    j(int);
14; };
15;
16; int  (B::*mp_f)(int)       = &B::f;
17; int  (B::*mp_g)(A, int, A) = &B::g;
18; void (B::*mp_h)(A, int, A) = &B::h;
19; A    (B::*mp_i)(A, int, A) = &B::i;
20; A    (B::*mp_j)(int)       = &B::j;
21
22; Each member pointer creates a thunk.  The ones with inalloca are required to
23; tail calls by the ABI, even at O0.
24
25%struct.B = type { i32 (...)** }
26%struct.A = type { i32 }
27
28; CHECK-LABEL: f_thunk:
29; CHECK: jmpl
30; CHECK-NOT: ret
31define x86_thiscallcc i32 @f_thunk(%struct.B* %this, i32) {
32entry:
33  %1 = bitcast %struct.B* %this to i32 (%struct.B*, i32)***
34  %vtable = load i32 (%struct.B*, i32)*** %1
35  %2 = load i32 (%struct.B*, i32)** %vtable
36  %3 = musttail call x86_thiscallcc i32 %2(%struct.B* %this, i32 %0)
37  ret i32 %3
38}
39
40; Inalloca thunks shouldn't require any stores to the stack.
41; CHECK-LABEL: g_thunk:
42; CHECK-NOT: mov %{{.*}}, {{.*(.*esp.*)}}
43; CHECK: jmpl
44; CHECK-NOT: ret
45define x86_thiscallcc i32 @g_thunk(%struct.B* %this, <{ %struct.A, i32, %struct.A }>* inalloca) {
46entry:
47  %1 = bitcast %struct.B* %this to i32 (%struct.B*, <{ %struct.A, i32, %struct.A }>*)***
48  %vtable = load i32 (%struct.B*, <{ %struct.A, i32, %struct.A }>*)*** %1
49  %vfn = getelementptr inbounds i32 (%struct.B*, <{ %struct.A, i32, %struct.A }>*)** %vtable, i32 1
50  %2 = load i32 (%struct.B*, <{ %struct.A, i32, %struct.A }>*)** %vfn
51  %3 = musttail call x86_thiscallcc i32 %2(%struct.B* %this, <{ %struct.A, i32, %struct.A }>* inalloca %0)
52  ret i32 %3
53}
54
55; CHECK-LABEL: h_thunk:
56; CHECK: jmpl
57; CHECK-NOT: mov %{{.*}}, {{.*(.*esp.*)}}
58; CHECK-NOT: ret
59define x86_thiscallcc void @h_thunk(%struct.B* %this, <{ %struct.A, i32, %struct.A }>* inalloca) {
60entry:
61  %1 = bitcast %struct.B* %this to void (%struct.B*, <{ %struct.A, i32, %struct.A }>*)***
62  %vtable = load void (%struct.B*, <{ %struct.A, i32, %struct.A }>*)*** %1
63  %vfn = getelementptr inbounds void (%struct.B*, <{ %struct.A, i32, %struct.A }>*)** %vtable, i32 2
64  %2 = load void (%struct.B*, <{ %struct.A, i32, %struct.A }>*)** %vfn
65  musttail call x86_thiscallcc void %2(%struct.B* %this, <{ %struct.A, i32, %struct.A }>* inalloca %0)
66  ret void
67}
68
69; CHECK-LABEL: i_thunk:
70; CHECK-NOT: mov %{{.*}}, {{.*(.*esp.*)}}
71; CHECK: jmpl
72; CHECK-NOT: ret
73define x86_thiscallcc %struct.A* @i_thunk(%struct.B* %this, <{ %struct.A*, %struct.A, i32, %struct.A }>* inalloca) {
74entry:
75  %1 = bitcast %struct.B* %this to %struct.A* (%struct.B*, <{ %struct.A*, %struct.A, i32, %struct.A }>*)***
76  %vtable = load %struct.A* (%struct.B*, <{ %struct.A*, %struct.A, i32, %struct.A }>*)*** %1
77  %vfn = getelementptr inbounds %struct.A* (%struct.B*, <{ %struct.A*, %struct.A, i32, %struct.A }>*)** %vtable, i32 3
78  %2 = load %struct.A* (%struct.B*, <{ %struct.A*, %struct.A, i32, %struct.A }>*)** %vfn
79  %3 = musttail call x86_thiscallcc %struct.A* %2(%struct.B* %this, <{ %struct.A*, %struct.A, i32, %struct.A }>* inalloca %0)
80  ret %struct.A* %3
81}
82
83; CHECK-LABEL: j_thunk:
84; CHECK: jmpl
85; CHECK-NOT: ret
86define x86_thiscallcc void @j_thunk(%struct.A* noalias sret %agg.result, %struct.B* %this, i32) {
87entry:
88  %1 = bitcast %struct.B* %this to void (%struct.A*, %struct.B*, i32)***
89  %vtable = load void (%struct.A*, %struct.B*, i32)*** %1
90  %vfn = getelementptr inbounds void (%struct.A*, %struct.B*, i32)** %vtable, i32 4
91  %2 = load void (%struct.A*, %struct.B*, i32)** %vfn
92  musttail call x86_thiscallcc void %2(%struct.A* sret %agg.result, %struct.B* %this, i32 %0)
93  ret void
94}
95
96; CHECK-LABEL: _stdcall_thunk@8:
97; CHECK-NOT: mov %{{.*}}, {{.*(.*esp.*)}}
98; CHECK: jmpl
99; CHECK-NOT: ret
100define x86_stdcallcc i32 @stdcall_thunk(<{ %struct.B*, %struct.A }>* inalloca) {
101entry:
102  %this_ptr = getelementptr inbounds <{ %struct.B*, %struct.A }>* %0, i32 0, i32 0
103  %this = load %struct.B** %this_ptr
104  %1 = bitcast %struct.B* %this to i32 (<{ %struct.B*, %struct.A }>*)***
105  %vtable = load i32 (<{ %struct.B*, %struct.A }>*)*** %1
106  %vfn = getelementptr inbounds i32 (<{ %struct.B*, %struct.A }>*)** %vtable, i32 1
107  %2 = load i32 (<{ %struct.B*, %struct.A }>*)** %vfn
108  %3 = musttail call x86_stdcallcc i32 %2(<{ %struct.B*, %struct.A }>* inalloca %0)
109  ret i32 %3
110}
111
112; CHECK-LABEL: @fastcall_thunk@8:
113; CHECK-NOT: mov %{{.*}}, {{.*(.*esp.*)}}
114; CHECK: jmpl
115; CHECK-NOT: ret
116define x86_fastcallcc i32 @fastcall_thunk(%struct.B* inreg %this, <{ %struct.A }>* inalloca) {
117entry:
118  %1 = bitcast %struct.B* %this to i32 (%struct.B*, <{ %struct.A }>*)***
119  %vtable = load i32 (%struct.B*, <{ %struct.A }>*)*** %1
120  %vfn = getelementptr inbounds i32 (%struct.B*, <{ %struct.A }>*)** %vtable, i32 1
121  %2 = load i32 (%struct.B*, <{ %struct.A }>*)** %vfn
122  %3 = musttail call x86_fastcallcc i32 %2(%struct.B* inreg %this, <{ %struct.A }>* inalloca %0)
123  ret i32 %3
124}
125