1# RUN: llc %s -mtriple=s390x-linux-gnu -mcpu=z13 \ 2# RUN: -start-before=register-coalescer -o - 2>&1 > /dev/null 3 4# Test that the SystemZ shouldCoalesce() implementation does not crash in 5# case of an undef use in another MBB. This was discovered in testing with 6# -systemz-subreg-liveness. 7 8--- | 9 @g_74 = external dso_local unnamed_addr global i32, align 4 10 @g_193 = external dso_local unnamed_addr global i32, align 4 11 12 define dso_local void @main() local_unnamed_addr { 13 %1 = load i32, ptr @g_193 14 %2 = or i32 %1, -1395153718 15 %3 = sdiv i32 -1395153718, %2 16 br i1 undef, label %5, label %4 17 18 ; <label>:4: ; preds = %0 19 store i32 %3, ptr @g_74 20 store i32 -9, ptr @g_74 21 ret void 22 23 ; <label>:5: ; preds = %0 24 unreachable 25 } 26 27... 28--- 29name: main 30alignment: 16 31tracksRegLiveness: true 32registers: 33 - { id: 0, class: grx32bit } 34 - { id: 1, class: addr64bit } 35 - { id: 2, class: gr32bit } 36 - { id: 3, class: gr32bit } 37 - { id: 4, class: gr64bit } 38 - { id: 5, class: gr128bit } 39 - { id: 6, class: gr128bit } 40 - { id: 7, class: grx32bit } 41 - { id: 8, class: gr32bit } 42 - { id: 9, class: gr128bit } 43body: | 44 bb.0 (%ir-block.0): 45 successors: %bb.2(0x00000001), %bb.1(0x7fffffff) 46 47 %1:addr64bit = LARL @g_193 48 %2:gr32bit = IIFMux 2899813578 49 %3:gr32bit = COPY killed %2 50 %3:gr32bit = O %3, killed %1, 0, $noreg, implicit-def dead $cc :: (dereferenceable load (s32) from @g_193) 51 %4:gr64bit = LGFI -1395153718 52 undef %5.subreg_l64:gr128bit = COPY killed %4 53 %6:gr128bit = COPY killed %5 54 dead %6:gr128bit = DSGFR %6, killed %3 55 %7:grx32bit = LHIMux 0 56 CHIMux killed %7, 0, implicit-def $cc 57 BRC 14, 6, %bb.2, implicit killed $cc 58 J %bb.1 59 60 bb.1 (%ir-block.4): 61 %8:gr32bit = LHIMux -9 62 STRL killed %8, @g_74 :: (store (s32) into @g_74) 63 Return 64 65 bb.2 (%ir-block.5): 66 dead %0:grx32bit = COPY undef %6.subreg_l32 67 68... 69