117 lines · python
1# Test 64-bit COMPARE AND BRANCH in cases where the sheer number of2# instructions causes some branches to be out of range.3# RUN: %python %s | llc -mtriple=s390x-linux-gnu | FileCheck %s4 5# Construct:6#7# before0:8# conditional branch to after09# ...10# beforeN:11# conditional branch to after012# main:13# 0xffcc bytes, from MVIY instructions14# conditional branch to main15# after0:16# ...17# conditional branch to main18# afterN:19#20# Each conditional branch sequence occupies 12 bytes if it uses a short21# branch and 16 if it uses a long one. The ones before "main:" have to22# take the branch length into account, which is 6 for short branches,23# so the final (0x34 - 6) / 12 == 3 blocks can use short branches.24# The ones after "main:" do not, so the first 0x34 / 12 == 4 blocks25# can use short branches. The conservative algorithm we use makes26# one of the forward branches unnecessarily long, as noted in the27# check output below.28#29# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)30# CHECK: cgr %r4, [[REG]]31# CHECK: jge [[LABEL:\.L[^ ]*]]32# CHECK: lgb [[REG:%r[0-5]]], 1(%r3)33# CHECK: cgr %r4, [[REG]]34# CHECK: jge [[LABEL]]35# CHECK: lgb [[REG:%r[0-5]]], 2(%r3)36# CHECK: cgr %r4, [[REG]]37# CHECK: jge [[LABEL]]38# CHECK: lgb [[REG:%r[0-5]]], 3(%r3)39# CHECK: cgr %r4, [[REG]]40# CHECK: jge [[LABEL]]41# CHECK: lgb [[REG:%r[0-5]]], 4(%r3)42# CHECK: cgr %r4, [[REG]]43# CHECK: jge [[LABEL]]44# ...as mentioned above, the next one could be a CGRJE instead...45# CHECK: lgb [[REG:%r[0-5]]], 5(%r3)46# CHECK: cgr %r4, [[REG]]47# CHECK: jge [[LABEL]]48# CHECK: lgb [[REG:%r[0-5]]], 6(%r3)49# CHECK: cgrje %r4, [[REG]], [[LABEL]]50# CHECK: lgb [[REG:%r[0-5]]], 7(%r3)51# CHECK: cgrje %r4, [[REG]], [[LABEL]]52# ...main goes here...53# CHECK: lgb [[REG:%r[0-5]]], 25(%r3)54# CHECK: cgrje %r4, [[REG]], [[LABEL:\.L[^ ]*]]55# CHECK: lgb [[REG:%r[0-5]]], 26(%r3)56# CHECK: cgrje %r4, [[REG]], [[LABEL]]57# CHECK: lgb [[REG:%r[0-5]]], 27(%r3)58# CHECK: cgrje %r4, [[REG]], [[LABEL]]59# CHECK: lgb [[REG:%r[0-5]]], 28(%r3)60# CHECK: cgrje %r4, [[REG]], [[LABEL]]61# CHECK: lgb [[REG:%r[0-5]]], 29(%r3)62# CHECK: cgr %r4, [[REG]]63# CHECK: jge [[LABEL]]64# CHECK: lgb [[REG:%r[0-5]]], 30(%r3)65# CHECK: cgr %r4, [[REG]]66# CHECK: jge [[LABEL]]67# CHECK: lgb [[REG:%r[0-5]]], 31(%r3)68# CHECK: cgr %r4, [[REG]]69# CHECK: jge [[LABEL]]70# CHECK: lgb [[REG:%r[0-5]]], 32(%r3)71# CHECK: cgr %r4, [[REG]]72# CHECK: jge [[LABEL]]73 74from __future__ import print_function75 76branch_blocks = 877main_size = 0xFFCC78 79print("@global = global i32 0")80 81print("define void @f1(i8 *%base, i8 *%stop, i64 %limit) {")82print("entry:")83print(" br label %before0")84print("")85 86for i in range(branch_blocks):87 next = "before%d" % (i + 1) if i + 1 < branch_blocks else "main"88 print("before%d:" % i)89 print(" %%bstop%d = getelementptr i8, i8 *%%stop, i64 %d" % (i, i))90 print(" %%bcur%d = load i8 , i8 *%%bstop%d" % (i, i))91 print(" %%bext%d = sext i8 %%bcur%d to i64" % (i, i))92 print(" %%btest%d = icmp eq i64 %%limit, %%bext%d" % (i, i))93 print(" br i1 %%btest%d, label %%after0, label %%%s" % (i, next))94 print("")95 96print("%s:" % next)97a, b = 1, 198for i in range(0, main_size, 6):99 a, b = b, a + b100 offset = 4096 + b % 500000101 value = a % 256102 print(" %%ptr%d = getelementptr i8, i8 *%%base, i64 %d" % (i, offset))103 print(" store volatile i8 %d, i8 *%%ptr%d" % (value, i))104 105for i in range(branch_blocks):106 print(" %%astop%d = getelementptr i8, i8 *%%stop, i64 %d" % (i, i + 25))107 print(" %%acur%d = load i8 , i8 *%%astop%d" % (i, i))108 print(" %%aext%d = sext i8 %%acur%d to i64" % (i, i))109 print(" %%atest%d = icmp eq i64 %%limit, %%aext%d" % (i, i))110 print(" br i1 %%atest%d, label %%main, label %%after%d" % (i, i))111 print("")112 print("after%d:" % i)113 114print(" %dummy = load volatile i32, i32 *@global")115print(" ret void")116print("}")117