test/CodeGen/SystemZ/Large/spill-02.py

   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
  23 from __future__ import print_function
  24
  25 args = (8168 - 160) / 8 + (5 - 1)
  26
  27 print('declare i64 *@foo(i64 *%s)' % (', i64' * args))
  28 print('declare void @bar(i64 *)')
  29 print('')
  30 print('define i64 @f1(i64 %foo) {')
  31 print('entry:')
  32
  33 # Make the allocation big, so that it goes at the top of the frame.
  34 print('  %array = alloca [1000 x i64]')
  35 print('  %area = getelementptr [1000 x i64], [1000 x i64] *%array, i64 0, i64 0')
  36 print('  %%base = call i64 *@foo(i64 *%%area%s)' % (', i64 0' * args))
  37 print('')
  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.
  41 count = 14
  42 for 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.
  49 for 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.
  57 print('  %cond = icmp eq i64 %val0, %val1')
  58 print('  br i1 %cond, label %skip, label %fallthru')
  59 print('')
  60 print('fallthru:')
  61 print('  store i64 %foo, i64 *%area')
  62 print('  store volatile i64 %val0, i64 *%ptr0')
  63 print('  br label %skip')
  64 print('')
  65 print('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.
  69 for 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
  74 print('  call void @bar(i64 *%area)')
  75 print('  ret i64 0')
  76 print('}')