xref: /llvm-project/llvm/test/CodeGen/SystemZ/Large/spill-02.py (revision b71edfaa4ec3c998aadb35255ce2f60bba2940b0)
1# Test cases where we spill from one frame index to another, both of which
2# are out of range of MVC, and both of which need emergency spill slots.
3# RUN: %python %s | llc -mtriple=s390x-linux-gnu | FileCheck %s
4
5# CHECK: f1:
6# CHECK: %fallthru
7# CHECK-DAG: stg [[REG1:%r[0-9]+]], 8168(%r15)
8# CHECK-DAG: stg [[REG2:%r[0-9]+]], 8176(%r15)
9# CHECK-DAG: lay [[REG3:%r[0-9]+]], 8192(%r15)
10# CHECK-DAG: lay [[REG4:%r[0-9]+]], 4096(%r15)
11# CHECK: mvc 0(8,[[REG3]]), 4088([[REG4]])
12# CHECK-DAG: lg [[REG1]], 8168(%r15)
13# CHECK-DAG: lg [[REG2]], 8176(%r15)
14# CHECK: %skip
15# CHECK: br %r14
16
17# Arrange for %foo's spill slot to be at 8184(%r15) and the alloca area to be at
18# 8192(%r15).  The two emergency spill slots live below that, so this requires
19# the first 8168 bytes to be used for the call.  160 of these bytes are
20# allocated for the ABI frame.  There are also 5 argument registers, one of
21# which is used as a base pointer.
22
23from __future__ import print_function
24
25args = int((8168 - 160) / 8 + (5 - 1))
26
27print("declare i64 *@foo(i64 *%s)" % (", i64" * args))
28print("declare void @bar(i64 *)")
29print("")
30print("define i64 @f1(i64 %foo) {")
31print("entry:")
32
33# Make the allocation big, so that it goes at the top of the frame.
34print("  %array = alloca [1000 x i64]")
35print("  %area = getelementptr [1000 x i64], [1000 x i64] *%array, i64 0, i64 0")
36print("  %%base = call i64 *@foo(i64 *%%area%s)" % (", i64 0" * args))
37print("")
38
39# Make sure all GPRs are used.  One is needed for the stack pointer and
40# another for %base, so we need 14 live values.
41count = 14
42for i in range(count):
43    print("  %%ptr%d = getelementptr i64, i64 *%%base, i64 %d" % (i, i / 2))
44    print("  %%val%d = load volatile i64 , i64 *%%ptr%d" % (i, i))
45    print("")
46
47# Encourage the register allocator to give preference to these %vals
48# by using them several times.
49for j in range(4):
50    for i in range(count):
51        print("  store volatile i64 %%val%d, i64 *%%ptr%d" % (i, i))
52    print("")
53
54# Copy the incoming argument, which we expect to be spilled, to the frame
55# index for the alloca area.  Also throw in a volatile store, so that this
56# block cannot be reordered with the surrounding code.
57print("  %cond = icmp eq i64 %val0, %val1")
58print("  br i1 %cond, label %skip, label %fallthru")
59print("")
60print("fallthru:")
61print("  store i64 %foo, i64 *%area")
62print("  store volatile i64 %val0, i64 *%ptr0")
63print("  br label %skip")
64print("")
65print("skip:")
66
67# Use each %val a few more times to emphasise the point, and to make sure
68# that they are live across the store of %foo.
69for j in range(4):
70    for i in range(count):
71        print("  store volatile i64 %%val%d, i64 *%%ptr%d" % (i, i))
72    print("")
73
74print("  call void @bar(i64 *%area)")
75print("  ret i64 0")
76print("}")
77