| ; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx908 -verify-machineinstrs -stop-after=amdgpu-isel -o - %s | FileCheck -check-prefix=GCN %s |
| define void @test() #1 { |
| ; Clean up the unreachable blocks introduced with LowerSwitch pass. |
| ; This test ensures that, in the pass flow, UnreachableBlockElim pass |
| ; follows the LowerSwitch. Otherwise, this testcase will crash |
| ; immediately after the instruction selection due to the incomplete |
| ; PHI node in an MBB whose incoming values were never codegenerated. |
| ; |
| ; GCN-LABEL: name: test |
| ; GCN: bb.{{[0-9]+}}.entry: |
| ; GCN: bb.{{[0-9]+}}.entry.true.blk: |
| ; GCN: bb.{{[0-9]+}}.entry.false.blk: |
| ; GCN: bb.{{[0-9]+}}.switch.blk: |
| |
| ; GCN-NOT: bb.{{[0-9]+}}.preheader.blk |
| ; GCN-NOT: bb.{{[0-9]+}}.pre.false.blk: |
| ; GCN-NOT: bb.{{[0-9]+}}.unreach.blk: |
| ; GCN-NOT: PHI |
| |
| ; GCN: bb.{{[0-9]+}}.exit: |
| entry: |
| %idx = tail call i32 @llvm.amdgcn.workitem.id.x() #0 |
| br i1 undef, label %entry.true.blk, label %entry.false.blk |
| |
| entry.true.blk: ; preds = %entry |
| %exit.cmp = icmp ult i32 %idx, 3 |
| br i1 %exit.cmp, label %switch.blk, label %exit |
| |
| entry.false.blk: ; preds = %entry |
| unreachable |
| |
| switch.blk: ; preds = %entry.true.blk |
| switch i32 %idx, label %preheader.blk [ |
| i32 0, label %exit |
| i32 1, label %exit |
| i32 2, label %exit |
| ] |
| |
| preheader.blk: ; preds = %switch.blk |
| %pre.exit = icmp ult i32 %idx, 5 |
| br i1 %pre.exit, label %unreach.blk, label %pre.false.blk |
| |
| pre.false.blk: ; preds = %preheader.blk |
| %call.pre.false = tail call i32 @func(i32 %idx) #0 |
| br label %unreach.blk |
| |
| unreach.blk: ; preds = %preheader.blk, %pre.false.blk |
| %phi.val = phi i32 [ %call.pre.false, %pre.false.blk ], [ undef, %preheader.blk ] |
| store i32 %phi.val, i32* undef |
| unreachable |
| |
| exit: ; preds = %switch.blk |
| ret void |
| } |
| |
| declare i32 @llvm.amdgcn.workitem.id.x() #0 |
| declare i32 @func(i32)#0 |
| |
| attributes #0 = { nounwind readnone } |
| attributes #1 = { nounwind } |