1# Verify PPC64 does not reuse a trampoline which is too far away.
2# This tests an edge case where the direct call relocation addend should
3# be ignored when computing the distance from the direct call to the
4# already placed trampoline
5[short] skip
6[!GOARCH:ppc64] [!GOARCH:ppc64le] skip
7[GOOS:aix] skip
8
9# Note, this program does not run. Presumably, 'DWORD $0' is simpler to
10# assembly 2^26 or so times.
11#
12# We build something which should be laid out as such:
13#
14# bar.Bar
15# main.Func1
16# bar.Bar+400-tramp0
17# main.BigAsm
18# main.Func2
19# bar.Bar+400-tramp1
20#
21# bar.Bar needs to be placed far enough away to generate relocations
22# from main package calls. and main.Func1 and main.Func2 are placed
23# a bit more than the direct call limit apart, but not more than 0x400
24# bytes beyond it (to verify the reloc calc).
25
26go build
27
28-- go.mod --
29
30module foo
31
32go 1.19
33
34-- main.go --
35
36package main
37
38import "foo/bar"
39
40func Func1()
41
42func main() {
43 Func1()
44 bar.Bar2()
45}
46
47-- foo.s --
48
49TEXT main·Func1(SB),0,$0-0
50 CALL bar·Bar+0x400(SB)
51 CALL main·BigAsm(SB)
52// A trampoline will be placed here to bar.Bar
53
54// This creates a gap sufficiently large to prevent trampoline reuse
55#define NOP64 DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0;
56#define NOP256 NOP64 NOP64 NOP64 NOP64
57#define NOP2S10 NOP256 NOP256 NOP256 NOP256
58#define NOP2S12 NOP2S10 NOP2S10 NOP2S10 NOP2S10
59#define NOP2S14 NOP2S12 NOP2S12 NOP2S12 NOP2S12
60#define NOP2S16 NOP2S14 NOP2S14 NOP2S14 NOP2S14
61#define NOP2S18 NOP2S16 NOP2S16 NOP2S16 NOP2S16
62#define NOP2S20 NOP2S18 NOP2S18 NOP2S18 NOP2S18
63#define NOP2S22 NOP2S20 NOP2S20 NOP2S20 NOP2S20
64#define NOP2S24 NOP2S22 NOP2S22 NOP2S22 NOP2S22
65#define BIGNOP NOP2S24 NOP2S24
66TEXT main·BigAsm(SB),0,$0-0
67 // Fill to the direct call limit so Func2 must generate a new trampoline.
68 // As the implicit trampoline above is just barely unreachable.
69 BIGNOP
70 MOVD $main·Func2(SB), R3
71
72TEXT main·Func2(SB),0,$0-0
73 CALL bar·Bar+0x400(SB)
74// Another trampoline should be placed here.
75
76-- bar/bar.s --
77
78#define NOP64 DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0; DWORD $0;
79#define NOP256 NOP64 NOP64 NOP64 NOP64
80#define NOP2S10 NOP256 NOP256 NOP256 NOP256
81#define NOP2S12 NOP2S10 NOP2S10 NOP2S10 NOP2S10
82#define NOP2S14 NOP2S12 NOP2S12 NOP2S12 NOP2S12
83#define NOP2S16 NOP2S14 NOP2S14 NOP2S14 NOP2S14
84#define NOP2S18 NOP2S16 NOP2S16 NOP2S16 NOP2S16
85#define NOP2S20 NOP2S18 NOP2S18 NOP2S18 NOP2S18
86#define NOP2S22 NOP2S20 NOP2S20 NOP2S20 NOP2S20
87#define NOP2S24 NOP2S22 NOP2S22 NOP2S22 NOP2S22
88#define BIGNOP NOP2S24 NOP2S24 NOP2S10
89// A very big not very interesting function.
90TEXT bar·Bar(SB),0,$0-0
91 BIGNOP
92
93-- bar/bar.go --
94
95package bar
96
97func Bar()
98
99func Bar2() {
100}
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