1; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx908 -verify-machineinstrs -stop-after=amdgpu-isel -o - %s | FileCheck -check-prefix=GCN %s 2define void @test(i1 %c0) #1 { 3 ; Clean up the unreachable blocks introduced with LowerSwitch pass. 4 ; This test ensures that, in the pass flow, UnreachableBlockElim pass 5 ; follows the LowerSwitch. Otherwise, this testcase will crash 6 ; immediately after the instruction selection due to the incomplete 7 ; PHI node in an MBB whose incoming values were never codegenerated. 8 ; 9 ; GCN-LABEL: name: test 10 ; GCN: bb.{{[0-9]+}}.entry: 11 ; GCN: bb.{{[0-9]+}}.Flow1: 12 ; GCN: bb.{{[0-9]+}}.entry.true.blk: 13 ; GCN: bb.{{[0-9]+}}.entry.false.blk: 14 ; GCN: bb.{{[0-9]+}}.switch.blk: 15 16 ; GCN-NOT: bb.{{[0-9]+}}.preheader.blk 17 ; GCN-NOT: bb.{{[0-9]+}}.pre.false.blk: 18 ; GCN-NOT: bb.{{[0-9]+}}.unreach.blk: 19 ; GCN-NOT: PHI 20 21 ; GCN: bb.{{[0-9]+}}.Flow: 22 ; GCN: bb.{{[0-9]+}}.UnifiedReturnBlock: 23 entry: 24 %idx = tail call i32 @llvm.amdgcn.workitem.id.x() #0 25 br i1 %c0, label %entry.true.blk, label %entry.false.blk 26 27 entry.true.blk: ; preds = %entry 28 %exit.cmp = icmp ult i32 %idx, 3 29 br i1 %exit.cmp, label %switch.blk, label %exit 30 31 entry.false.blk: ; preds = %entry 32 unreachable 33 34 switch.blk: ; preds = %entry.true.blk 35 switch i32 %idx, label %preheader.blk [ 36 i32 0, label %exit 37 i32 1, label %exit 38 i32 2, label %exit 39 ] 40 41 preheader.blk: ; preds = %switch.blk 42 %pre.exit = icmp ult i32 %idx, 5 43 br i1 %pre.exit, label %unreach.blk, label %pre.false.blk 44 45 pre.false.blk: ; preds = %preheader.blk 46 %call.pre.false = tail call i32 @func(i32 %idx) #0 47 br label %unreach.blk 48 49 unreach.blk: ; preds = %preheader.blk, %pre.false.blk 50 %phi.val = phi i32 [ %call.pre.false, %pre.false.blk ], [ undef, %preheader.blk ] 51 store i32 %phi.val, ptr undef 52 unreachable 53 54 exit: ; preds = %switch.blk 55 ret void 56} 57 58declare i32 @llvm.amdgcn.workitem.id.x() #0 59declare i32 @func(i32)#0 60 61attributes #0 = { nounwind readnone } 62attributes #1 = { nounwind } 63