xref: /llvm-project/llvm/test/CodeGen/X86/statepoint-stack-usage.ll (revision 189900eb149bb55ae3787346f57c1ccbdc50fb3c)
1; RUN: llc -verify-machineinstrs -stack-symbol-ordering=0 < %s | FileCheck %s
2
3target datalayout = "e-i64:64-f80:128-n8:16:32:64-S128"
4target triple = "x86_64-pc-linux-gnu"
5
6; This test is checking to make sure that we reuse the same stack slots
7; for GC values spilled over two different call sites.  Since the order
8; of GC arguments differ, niave lowering code would insert loads and
9; stores to rearrange items on the stack.  We need to make sure (for
10; performance) that this doesn't happen.
11define i32 @back_to_back_calls(ptr addrspace(1) %a, ptr addrspace(1) %b, ptr addrspace(1) %c) #1 gc "statepoint-example" {
12; CHECK-LABEL: back_to_back_calls
13; The exact stores don't matter, but there need to be three stack slots created
14; CHECK-DAG: movq	%rdi, {{[0-9]*}}(%rsp)
15; CHECK-DAG: movq	%rdx, {{[0-9]*}}(%rsp)
16; CHECK-DAG: movq	%rsi, {{[0-9]*}}(%rsp)
17; There should be no more than three moves
18; CHECK-NOT: movq
19  %safepoint_token = tail call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["gc-live" (ptr addrspace(1) %a, ptr addrspace(1) %b, ptr addrspace(1) %c), "deopt" (i32 0, i32 -1, i32 0, i32 0, i32 0)]
20  %a1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 0)
21  %b1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 1)
22  %c1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 2)
23; CHECK: callq
24; This is the key check.  There should NOT be any memory moves here
25; CHECK-NOT: movq
26  %safepoint_token2 = tail call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["gc-live" (ptr addrspace(1) %c1, ptr addrspace(1) %b1, ptr addrspace(1) %a1), "deopt" (i32 0, i32 -1, i32 0, i32 0, i32 0)]
27  %a2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 2)
28  %b2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 1)
29  %c2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 0)
30; CHECK: callq
31  ret i32 1
32}
33
34; This test simply checks that minor changes in vm state don't prevent slots
35; being reused for gc values.
36define i32 @reserve_first(ptr addrspace(1) %a, ptr addrspace(1) %b, ptr addrspace(1) %c) #1 gc "statepoint-example" {
37; CHECK-LABEL: reserve_first
38; The exact stores don't matter, but there need to be three stack slots created
39; CHECK-DAG: movq	%rdi, {{[0-9]*}}(%rsp)
40; CHECK-DAG: movq	%rdx, {{[0-9]*}}(%rsp)
41; CHECK-DAG: movq	%rsi, {{[0-9]*}}(%rsp)
42  %safepoint_token = tail call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["gc-live" (ptr addrspace(1) %a, ptr addrspace(1) %b, ptr addrspace(1) %c), "deopt" (i32 0, i32 -1, i32 0, i32 0, i32 0)]
43  %a1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 0)
44  %b1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 1)
45  %c1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 2)
46; CHECK: callq
47; This is the key check.  There should NOT be any memory moves here
48; CHECK-NOT: movq
49  %safepoint_token2 = tail call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["gc-live" (ptr addrspace(1) %c1, ptr addrspace(1) %b1, ptr addrspace(1) %a1), "deopt" (ptr addrspace(1) %a1, i32 0, ptr addrspace(1) %c1, i32 0, i32 0)]
50  %a2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 2)
51  %b2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 1)
52  %c2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 0)
53; CHECK: callq
54  ret i32 1
55}
56
57; Check that we reuse the same stack slot across multiple calls.  The use of
58; more than two calls here is critical.  We've had a bug which allowed reuse
59; exactly once which went undetected for a long time.
60define i32 @back_to_back_deopt(i32 %a, i32 %b, i32 %c) #1
61  gc "statepoint-example" {
62; CHECK-LABEL: back_to_back_deopt
63; The exact stores don't matter, but there need to be three stack slots created
64; CHECK-DAG: movl	%edi, 12(%rsp)
65; CHECK-DAG: movl	%esi, 8(%rsp)
66; CHECK-DAG: movl	%edx, 4(%rsp)
67; CHECK: callq
68; CHECK-DAG: movl	%r14d, 12(%rsp)
69; CHECK-DAG: movl	%ebp, 8(%rsp)
70; CHECK-DAG: movl	%ebx, 4(%rsp)
71; CHECK: callq
72; CHECK-DAG: movl	%r14d, 12(%rsp)
73; CHECK-DAG: movl	%ebp, 8(%rsp)
74; CHECK-DAG: movl	%ebx, 4(%rsp)
75; CHECK: callq
76; CHECK-DAG: movl	%r14d, 12(%rsp)
77; CHECK-DAG: movl	%ebp, 8(%rsp)
78; CHECK-DAG: movl	%ebx, 4(%rsp)
79; CHECK: callq
80  call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["deopt" (i32 %a, i32 %b, i32 %c)]
81call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["deopt" (i32 %a, i32 %b, i32 %c)]
82call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["deopt" (i32 %a, i32 %b, i32 %c)]
83call token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["deopt" (i32 %a, i32 %b, i32 %c)]
84  ret i32 1
85}
86
87; Test that stack slots are reused for invokes
88define i32 @back_to_back_invokes(ptr addrspace(1) %a, ptr addrspace(1) %b, ptr addrspace(1) %c) #1 gc "statepoint-example" personality ptr @"personality_function" {
89; CHECK-LABEL: back_to_back_invokes
90entry:
91  ; The exact stores don't matter, but there need to be three stack slots created
92  ; CHECK-DAG: movq	%rdi, {{[0-9]*}}(%rsp)
93  ; CHECK-DAG: movq	%rdx, {{[0-9]*}}(%rsp)
94  ; CHECK-DAG: movq	%rsi, {{[0-9]*}}(%rsp)
95  ; CHECK: callq
96  %safepoint_token = invoke token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["gc-live" (ptr addrspace(1) %a, ptr addrspace(1) %b, ptr addrspace(1) %c), "deopt" (i32 0, i32 -1, i32 0, i32 0, i32 0)]
97                   to label %normal_return unwind label %exceptional_return
98
99normal_return:
100  %a1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 0)
101  %b1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 1)
102  %c1 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token, i32 0, i32 2)
103  ; Should work even through bitcasts
104  ; This is the key check.  There should NOT be any memory moves here
105  ; CHECK-NOT: movq
106  ; CHECK: callq
107  %safepoint_token2 = invoke token (i64, i32, ptr, i32, i32, ...) @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) undef, i32 0, i32 0, i32 0, i32 0) ["gc-live" (ptr addrspace(1) %c1, ptr addrspace(1) %b1, ptr addrspace(1) %a1), "deopt" (i32 0, i32 -1, i32 0, i32 0, i32 0)]
108                    to label %normal_return2 unwind label %exceptional_return2
109
110normal_return2:
111  %a2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 2)
112  %b2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 1)
113  %c2 = tail call coldcc ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token %safepoint_token2, i32 0, i32 0)
114  ret i32 1
115
116exceptional_return:
117  %landing_pad = landingpad { ptr, i32 }
118          cleanup
119  ret i32 0
120
121exceptional_return2:
122  %landing_pad2 = landingpad { ptr, i32 }
123          cleanup
124  ret i32 0
125}
126
127; Function Attrs: nounwind
128declare ptr addrspace(1) @llvm.experimental.gc.relocate.p1(token, i32, i32) #3
129
130declare token @llvm.experimental.gc.statepoint.p0(i64, i32, ptr, i32, i32, ...)
131
132declare i32 @"personality_function"()
133
134attributes #1 = { uwtable }
135