1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
# RUN: llc -mtriple=x86_64-unknown-unknown %s -o - -run-pass=livedebugvalues | FileCheck %s
#
# Fix some of PR42772. Consider the code below: the arguments are forced onto
# the stack by the FORCE_SPILL macro, and go out of liveness if the
# "bees == 2" conditional is not taken. A spill slot is then re-used to
# preserve quux over the second FORCE_SPILL, over-writing the value of either
# "a" or "b". LiveDebugValues should detect when this happens, and terminate
# stack-spill locations when they get overwritten by a new value.
#
# --------8<--------
# #define FORCE_SPILL() \
# __asm volatile("" : : : \
# "rax", "rbx", "rcx", "rdx", "rsi", "rdi", "rbp", "r8", \
# "r9", "r10", "r11", "r12", "r13", "r14", "r15")
#
# volatile int bees = 0;
#
# long int f(long int a, long int b) {
# if (bees == 12)
# return 3;
#
# FORCE_SPILL();
# if (bees == 2)
# return a - b;
#
# int quux = sum(1, 2);
# FORCE_SPILL();
# bees++;
# return quux;
# }
# -------->8--------
#
# CHECK: ![[ANUM:[0-9]+]] = !DILocalVariable(name: "a"
# CHECK: ![[BNUM:[0-9]+]] = !DILocalVariable(name: "b"
#
# These variables should be spilt,
# CHECK-LABEL: bb.1.if.end:
# CHECK: MOV64mr $rsp, 1, $noreg, 16, $noreg, killed renamable $rsi
# CHECK-NEXT: DBG_VALUE $rsp, 0, ![[BNUM]], !DIExpression(
# CHECK-NEXT: MOV64mr $rsp, 1, $noreg, 8, $noreg, killed renamable $rdi
# CHECK-NEXT: DBG_VALUE $rsp, 0, ![[ANUM]], !DIExpression(
# CHECK-NEXT: INLINEASM
#
# Then the location of "a" should be terminated when overwritten
# CHECK-LABEL: bb.3.if.end3:
# CHECK: CALL64pcrel32 @sum
# CHECK-NEXT: MOV64mr $rsp, 1, $noreg, 8, $noreg, $rax
# CHECK-NEXT: DBG_VALUE $noreg, $noreg, ![[ANUM]], !DIExpression()
# CHECK-NEXT: INLINEASM
--- |
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@bees = external global i32, !dbg !0
; Function Attrs: noinline norecurse nounwind readnone uwtable
declare i64 @sum(i64, i64)
; Function Attrs: noinline nounwind uwtable
define i64 @f(i64 %a, i64 %b) !dbg !12 {
entry:
br label %if.end
if.end:
br label %if.then2
if.then2:
br label %if.end3
if.end3:
br label %return
return:
ret i64 0
}
!llvm.dbg.cu = !{!2}
!llvm.module.flags = !{!8, !9, !10}
!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
!1 = distinct !DIGlobalVariable(name: "bees", scope: !2, file: !3, line: 6, type: !6, isLocal: false, isDefinition: true)
!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5, nameTableKind: None)
!3 = !DIFile(filename: "pr42772.c", directory: ".")
!4 = !{}
!5 = !{!0}
!6 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !7)
!7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!8 = !{i32 2, !"Dwarf Version", i32 4}
!9 = !{i32 2, !"Debug Info Version", i32 3}
!10 = !{i32 1, !"wchar_size", i32 4}
!12 = distinct !DISubprogram(name: "f", scope: !3, file: !3, line: 15, type: !13, scopeLine: 15, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !16)
!13 = !DISubroutineType(types: !14)
!14 = !{!15, !15, !15}
!15 = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
!16 = !{!17, !18, !19}
!17 = !DILocalVariable(name: "a", arg: 1, scope: !12, file: !3, line: 15, type: !15)
!18 = !DILocalVariable(name: "b", arg: 2, scope: !12, file: !3, line: 15, type: !15)
!19 = !DILocalVariable(name: "quux", scope: !12, file: !3, line: 23, type: !7)
!28 = !DILocation(line: 1, column: 1, scope: !12)
...
---
name: f
tracksRegLiveness: true
liveins:
- { reg: '$rdi', virtual-reg: '' }
- { reg: '$rsi', virtual-reg: '' }
frameInfo:
stackSize: 72
offsetAdjustment: -72
maxAlignment: 8
adjustsStack: true
hasCalls: true
cvBytesOfCalleeSavedRegisters: 48
fixedStack:
- { id: 0, type: spill-slot, offset: -56, size: 8, alignment: 8, stack-id: default,
callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
- { id: 1, type: spill-slot, offset: -48, size: 8, alignment: 16, stack-id: default,
callee-saved-register: '$r12', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
- { id: 2, type: spill-slot, offset: -40, size: 8, alignment: 8, stack-id: default,
callee-saved-register: '$r13', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
- { id: 3, type: spill-slot, offset: -32, size: 8, alignment: 16, stack-id: default,
callee-saved-register: '$r14', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
- { id: 4, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default,
callee-saved-register: '$r15', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
- { id: 5, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
callee-saved-register: '$rbp', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
stack:
- { id: 0, name: '', type: spill-slot, offset: -72, size: 8, alignment: 8,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 1, name: '', type: spill-slot, offset: -64, size: 8, alignment: 8,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body: |
bb.0.entry:
successors: %bb.4, %bb.1
liveins: $rdi, $rsi, $rbp, $r15, $r14, $r13, $r12, $rbx
DBG_VALUE $rdi, $noreg, !17, !DIExpression(), debug-location !28
DBG_VALUE $rdi, $noreg, !17, !DIExpression(), debug-location !28
DBG_VALUE $rsi, $noreg, !18, !DIExpression(), debug-location !28
DBG_VALUE $rsi, $noreg, !18, !DIExpression(), debug-location !28
frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp, debug-location !28
frame-setup PUSH64r killed $r15, implicit-def $rsp, implicit $rsp, debug-location !28
frame-setup PUSH64r killed $r14, implicit-def $rsp, implicit $rsp, debug-location !28
frame-setup PUSH64r killed $r13, implicit-def $rsp, implicit $rsp, debug-location !28
frame-setup PUSH64r killed $r12, implicit-def $rsp, implicit $rsp, debug-location !28
frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp, debug-location !28
$rsp = frame-setup SUB64ri8 $rsp, 24, implicit-def dead $eflags
renamable $ecx = MOV32rm $rip, 1, $noreg, @bees, $noreg, debug-location !28 :: (volatile dereferenceable load (s32) from @bees)
$eax = MOV32ri 3, implicit-def $rax
CMP32ri8 killed renamable $ecx, 12, implicit-def $eflags, debug-location !28
JCC_1 %bb.4, 4, implicit $eflags, debug-location !28
bb.1.if.end:
successors: %bb.2, %bb.3
liveins: $rdi, $rsi
MOV64mr $rsp, 1, $noreg, 16, $noreg, killed renamable $rsi :: (store (s64) into %stack.1)
MOV64mr $rsp, 1, $noreg, 8, $noreg, killed renamable $rdi :: (store (s64) into %stack.0)
INLINEASM &"", 1, 12, implicit-def dead early-clobber $rax, 12, implicit-def dead early-clobber $rbx, 12, implicit-def dead early-clobber $rcx, 12, implicit-def dead early-clobber $rdx, 12, implicit-def dead early-clobber $rsi, 12, implicit-def dead early-clobber $rdi, 12, implicit-def dead early-clobber $rbp, 12, implicit-def dead early-clobber $r8, 12, implicit-def dead early-clobber $r9, 12, implicit-def dead early-clobber $r10, 12, implicit-def dead early-clobber $r11, 12, implicit-def dead early-clobber $r12, 12, implicit-def dead early-clobber $r13, 12, implicit-def dead early-clobber $r14, 12, implicit-def dead early-clobber $r15, 12, implicit-def dead early-clobber $df, 12, implicit-def dead early-clobber $fpsw, 12, implicit-def dead early-clobber $eflags, debug-location !28
renamable $eax = MOV32rm $rip, 1, $noreg, @bees, $noreg, debug-location !28 :: (volatile dereferenceable load (s32) from @bees)
CMP32ri8 killed renamable $eax, 2, implicit-def $eflags, debug-location !28
JCC_1 %bb.3, 5, implicit killed $eflags, debug-location !28
bb.2.if.then2:
successors: %bb.4
renamable $rax = MOV64rm $rsp, 1, $noreg, 8, $noreg :: (load (s64) from %stack.0)
renamable $rax = SUB64rm killed renamable $rax, $rsp, 1, $noreg, 16, $noreg, implicit-def dead $eflags, debug-location !28 :: (load (s64) from %stack.1)
JMP_1 %bb.4
bb.3.if.end3:
successors: %bb.4
$edi = MOV32ri 1, implicit-def $rdi, debug-location !28
$esi = MOV32ri 2, implicit-def $rsi, debug-location !28
CALL64pcrel32 @sum, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit $rsi, implicit-def $rsp, implicit-def $ssp, implicit-def $rax, debug-location !28
MOV64mr $rsp, 1, $noreg, 8, $noreg, $rax :: (store (s64) into %stack.0)
INLINEASM &"", 1, 12, implicit-def dead early-clobber $rax, 12, implicit-def dead early-clobber $rbx, 12, implicit-def dead early-clobber $rcx, 12, implicit-def dead early-clobber $rdx, 12, implicit-def dead early-clobber $rsi, 12, implicit-def dead early-clobber $rdi, 12, implicit-def dead early-clobber $rbp, 12, implicit-def dead early-clobber $r8, 12, implicit-def dead early-clobber $r9, 12, implicit-def dead early-clobber $r10, 12, implicit-def dead early-clobber $r11, 12, implicit-def dead early-clobber $r12, 12, implicit-def dead early-clobber $r13, 12, implicit-def dead early-clobber $r14, 12, implicit-def dead early-clobber $r15, 12, implicit-def dead early-clobber $df, 12, implicit-def dead early-clobber $fpsw, 12, implicit-def dead early-clobber $eflags, debug-location !28
ADD32mi8 $rip, 1, $noreg, @bees, $noreg, 1, implicit-def dead $eflags, debug-location !28 :: (volatile store (s32) into @bees), (volatile dereferenceable load (s32) from @bees)
renamable $rax = MOVSX64rm32 $rsp, 1, $noreg, 8, $noreg, debug-location !28 :: (load (s32) from %stack.0, align 8)
bb.4.return:
liveins: $rax
$rsp = frame-destroy ADD64ri8 $rsp, 24, implicit-def dead $eflags, debug-location !28
$rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
$r12 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
$r13 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
$r14 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
$r15 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
$rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
RET64 $rax, debug-location !28
...
|
