[AMDGPU] Unify unreachable intrinsics

si-annotate-control-flow does depth first traversal of BB's of
a function to insert amdgcn if intrinsics for conditional
branches so that isel can generate correct instructions later.

si-annotate-control-flow checks whether the successor BB for the 'else'
branch of a conditional branch has been visited. If it has been
visited, si-annotate-control-flow assumes the conditional
branch has been handled and will not try to insert if intrinsic
for it.

This assumption is not correct when the IR contains multiple
unreachable BB's. Then 'if' intrinscs are not inserted and incorrect
ISA are generated.

This patch fixes the issue by let amdgpu-unify-divergent-exit-nodes
unify unreachables even if they are uniformly reached. In this way
the IR will not contain multiple exits, and structurizer is able to
structurize the IR containing one unified exit.

Reviewed by: Ruiling Song, Matt Arsenault

Differential Revision: https://reviews.llvm.org/D131181

Fixes: SWDEV-343244

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp b/llvm/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp
index c6751f9..9adcb9b 100644 (file)
--- a/llvm/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUUnifyDivergentExitNodes.cpp
@@ -211,8 +211,12 @@ bool AMDGPUUnifyDivergentExitNodes::runOnFunction(Function &F) {
       if (!isUniformlyReached(DA, *BB))
         ReturningBlocks.push_back(BB);
     } else if (isa<UnreachableInst>(BB->getTerminator())) {
-      if (!isUniformlyReached(DA, *BB))
-        UnreachableBlocks.push_back(BB);
+      // TODO: For now we unify UnreachableBlocks even though they are uniformly
+      // reachable. This is to workaround the limitation of structurizer, which
+      // can not handle multiple function exits. After structurizer is able to
+      // handle multiple function exits, we should only unify UnreachableBlocks
+      // that are not uniformly reachable.
+      UnreachableBlocks.push_back(BB);
     } else if (BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator())) {
 
       ConstantInt *BoolTrue = ConstantInt::getTrue(F.getContext());

diff --git a/llvm/test/CodeGen/AMDGPU/GlobalISel/bool-legalization.ll b/llvm/test/CodeGen/AMDGPU/GlobalISel/bool-legalization.ll
index f4d8b81..cfc58aa 100644 (file)
--- a/llvm/test/CodeGen/AMDGPU/GlobalISel/bool-legalization.ll
+++ b/llvm/test/CodeGen/AMDGPU/GlobalISel/bool-legalization.ll
@@ -50,20 +50,28 @@ define amdgpu_ps i32 @select_sgpr_trunc_and_cond(i32 inreg %a.0, i32 inreg %a.1,
 define amdgpu_kernel void @sgpr_trunc_brcond(i32 %cond) {
 ; GCN-LABEL: sgpr_trunc_brcond:
 ; GCN:       ; %bb.0: ; %entry
-; GCN-NEXT:    s_load_dword s0, s[0:1], 0x9
+; GCN-NEXT:    s_load_dword s1, s[0:1], 0x9
+; GCN-NEXT:    s_mov_b32 s0, -1
 ; GCN-NEXT:    s_waitcnt lgkmcnt(0)
+; GCN-NEXT:    s_xor_b32 s1, s1, -1
+; GCN-NEXT:    s_and_b32 s1, s1, 1
+; GCN-NEXT:    s_cmp_lg_u32 s1, 0
+; GCN-NEXT:    s_cbranch_scc0 .LBB3_2
+; GCN-NEXT:  ; %bb.1: ; %bb1
+; GCN-NEXT:    v_mov_b32_e32 v0, 1
+; GCN-NEXT:    s_mov_b32 s0, 0
+; GCN-NEXT:    flat_store_dword v[0:1], v0
+; GCN-NEXT:    s_waitcnt vmcnt(0)
+; GCN-NEXT:  .LBB3_2: ; %Flow
 ; GCN-NEXT:    s_xor_b32 s0, s0, -1
 ; GCN-NEXT:    s_and_b32 s0, s0, 1
 ; GCN-NEXT:    s_cmp_lg_u32 s0, 0
-; GCN-NEXT:    s_cbranch_scc1 .LBB3_2
-; GCN-NEXT:  ; %bb.1: ; %bb0
+; GCN-NEXT:    s_cbranch_scc1 .LBB3_4
+; GCN-NEXT:  ; %bb.3: ; %bb0
 ; GCN-NEXT:    v_mov_b32_e32 v0, 0
 ; GCN-NEXT:    flat_store_dword v[0:1], v0
 ; GCN-NEXT:    s_waitcnt vmcnt(0)
-; GCN-NEXT:  .LBB3_2: ; %bb1
-; GCN-NEXT:    v_mov_b32_e32 v0, 1
-; GCN-NEXT:    flat_store_dword v[0:1], v0
-; GCN-NEXT:    s_waitcnt vmcnt(0)
+; GCN-NEXT:  .LBB3_4: ; %UnifiedUnreachableBlock
 entry:
   %trunc = trunc i32 %cond to i1
   br i1 %trunc, label %bb0, label %bb1
@@ -82,19 +90,27 @@ define amdgpu_kernel void @brcond_sgpr_trunc_and(i32 %cond0, i32 %cond1) {
 ; GCN:       ; %bb.0: ; %entry
 ; GCN-NEXT:    s_load_dwordx2 s[0:1], s[0:1], 0x9
 ; GCN-NEXT:    s_waitcnt lgkmcnt(0)
-; GCN-NEXT:    s_and_b32 s0, s0, s1
+; GCN-NEXT:    s_and_b32 s1, s0, s1
+; GCN-NEXT:    s_xor_b32 s1, s1, -1
+; GCN-NEXT:    s_and_b32 s1, s1, 1
+; GCN-NEXT:    s_mov_b32 s0, -1
+; GCN-NEXT:    s_cmp_lg_u32 s1, 0
+; GCN-NEXT:    s_cbranch_scc0 .LBB4_2
+; GCN-NEXT:  ; %bb.1: ; %bb1
+; GCN-NEXT:    v_mov_b32_e32 v0, 1
+; GCN-NEXT:    s_mov_b32 s0, 0
+; GCN-NEXT:    flat_store_dword v[0:1], v0
+; GCN-NEXT:    s_waitcnt vmcnt(0)
+; GCN-NEXT:  .LBB4_2: ; %Flow
 ; GCN-NEXT:    s_xor_b32 s0, s0, -1
 ; GCN-NEXT:    s_and_b32 s0, s0, 1
 ; GCN-NEXT:    s_cmp_lg_u32 s0, 0
-; GCN-NEXT:    s_cbranch_scc1 .LBB4_2
-; GCN-NEXT:  ; %bb.1: ; %bb0
+; GCN-NEXT:    s_cbranch_scc1 .LBB4_4
+; GCN-NEXT:  ; %bb.3: ; %bb0
 ; GCN-NEXT:    v_mov_b32_e32 v0, 0
 ; GCN-NEXT:    flat_store_dword v[0:1], v0
 ; GCN-NEXT:    s_waitcnt vmcnt(0)
-; GCN-NEXT:  .LBB4_2: ; %bb1
-; GCN-NEXT:    v_mov_b32_e32 v0, 1
-; GCN-NEXT:    flat_store_dword v[0:1], v0
-; GCN-NEXT:    s_waitcnt vmcnt(0)
+; GCN-NEXT:  .LBB4_4: ; %UnifiedUnreachableBlock
 entry:
   %trunc0 = trunc i32 %cond0 to i1
   %trunc1 = trunc i32 %cond1 to i1

diff --git a/llvm/test/CodeGen/AMDGPU/si-unify-exit-multiple-unreachables.ll b/llvm/test/CodeGen/AMDGPU/si-unify-exit-multiple-unreachables.ll
new file mode 100644 (file)
index 0000000..6de2519
--- /dev/null
+++ b/llvm/test/CodeGen/AMDGPU/si-unify-exit-multiple-unreachables.ll
@@ -0,0 +1,138 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=amdgcn-amd-amdhsa -mcpu=gfx906 -stop-after=amdgpu-unify-divergent-exit-nodes | FileCheck %s --check-prefix=UNIFY
+; RUN: llc < %s -mtriple=amdgcn-amd-amdhsa -mcpu=gfx906 -verify-machineinstrs | FileCheck %s
+
+declare void @llvm.trap()
+declare i32 @llvm.amdgcn.workitem.id.x()
+
+define amdgpu_kernel void @kernel(i32 %a, i32 addrspace(1)* %x, i32 noundef %n) {
+; This used to bypass the structurization process because structurizer is unable to
+; handle multiple-exits CFG. This should be correctly structurized.
+; UNIFY-LABEL: define amdgpu_kernel void @kernel
+; UNIFY-LABEL: entry:
+; UNIFY:         %tid = call i32 @llvm.amdgcn.workitem.id.x()
+; UNIFY-NEXT:    %cmp = icmp eq i32 %n.load, 256
+; UNIFY-NEXT:    br i1 %cmp, label %if.then, label %if.else
+; UNIFY-LABEL: if.then:
+; UNIFY-NEXT:    %cmp1 = icmp eq i32 %a.load, 0
+; UNIFY-NEXT:    br i1 %cmp1, label %if.end6.sink.split, label %cond.false
+; UNIFY-LABEL: cond.false:
+; UNIFY-NEXT:    call void @llvm.trap()
+; UNIFY-NEXT:    br label %UnifiedUnreachableBlock
+; UNIFY-LABEL: if.else:
+; UNIFY-NEXT:    %cmp2 = icmp ult i32 %tid, 10
+; UNIFY-NEXT:    br i1 %cmp2, label %if.then3, label %UnifiedReturnBlock
+; UNIFY-LABEL: if.then3:
+; UNIFY-NEXT:    %cmp1.i7 = icmp eq i32 %a.load, 0
+; UNIFY-NEXT:    br i1 %cmp1.i7, label %if.end6.sink.split, label %cond.false.i8
+; UNIFY-LABEL: cond.false.i8:
+; UNIFY-NEXT:    call void @llvm.trap()
+; UNIFY-NEXT:    br label %UnifiedUnreachableBlock
+; UNIFY-LABEL: if.end6.sink.split:
+; UNIFY-NEXT:    %idxprom = sext i32 %tid to i64
+; UNIFY-NEXT:    %x1 = getelementptr inbounds i32, i32 addrspace(1)* %x.load, i64 %idxprom
+; UNIFY-NEXT:    store i32 %a.load, i32 addrspace(1)* %x1, align 4
+; UNIFY-NEXT:    br label %UnifiedReturnBlock
+; UNIFY-LABEL: UnifiedUnreachableBlock:
+; UNIFY-NEXT:    call void @llvm.amdgcn.unreachable()
+; UNIFY-NEXT:    br label %UnifiedReturnBlock
+; UNIFY-LABEL: UnifiedReturnBlock:
+; UNIFY-NEXT:    ret void
+
+; CHECK-LABEL: kernel:
+; CHECK:       ; %bb.0: ; %entry
+; CHECK-NEXT:    s_load_dword s0, s[4:5], 0x10
+; CHECK-NEXT:    s_load_dword s10, s[4:5], 0x0
+; CHECK-NEXT:    s_waitcnt lgkmcnt(0)
+; CHECK-NEXT:    s_cmpk_lg_i32 s0, 0x100
+; CHECK-NEXT:    s_cbranch_scc0 .LBB0_6
+; CHECK-NEXT:  ; %bb.1: ; %if.else
+; CHECK-NEXT:    v_cmp_gt_u32_e32 vcc, 10, v0
+; CHECK-NEXT:    s_mov_b64 s[6:7], 0
+; CHECK-NEXT:    s_mov_b64 s[2:3], 0
+; CHECK-NEXT:    s_mov_b64 s[0:1], 0
+; CHECK-NEXT:    s_and_saveexec_b64 s[8:9], vcc
+; CHECK-NEXT:    s_cbranch_execz .LBB0_5
+; CHECK-NEXT:  ; %bb.2: ; %if.then3
+; CHECK-NEXT:    s_cmp_lg_u32 s10, 0
+; CHECK-NEXT:    s_cbranch_scc1 .LBB0_14
+; CHECK-NEXT:  ; %bb.3:
+; CHECK-NEXT:    s_mov_b64 s[2:3], 0
+; CHECK-NEXT:    s_mov_b64 s[0:1], -1
+; CHECK-NEXT:  .LBB0_4: ; %Flow3
+; CHECK-NEXT:    s_and_b64 s[0:1], s[0:1], exec
+; CHECK-NEXT:    s_and_b64 s[2:3], s[2:3], exec
+; CHECK-NEXT:  .LBB0_5: ; %Flow2
+; CHECK-NEXT:    s_or_b64 exec, exec, s[8:9]
+; CHECK-NEXT:    s_and_b64 vcc, exec, s[6:7]
+; CHECK-NEXT:    s_cbranch_vccz .LBB0_8
+; CHECK-NEXT:    s_branch .LBB0_7
+; CHECK-NEXT:  .LBB0_6:
+; CHECK-NEXT:    s_mov_b64 s[2:3], 0
+; CHECK-NEXT:    s_mov_b64 s[0:1], 0
+; CHECK-NEXT:    s_cbranch_execz .LBB0_8
+; CHECK-NEXT:  .LBB0_7: ; %if.then
+; CHECK-NEXT:    s_cmp_lg_u32 s10, 0
+; CHECK-NEXT:    s_mov_b64 s[0:1], -1
+; CHECK-NEXT:    s_cbranch_scc1 .LBB0_13
+; CHECK-NEXT:  .LBB0_8: ; %Flow4
+; CHECK-NEXT:    s_and_saveexec_b64 s[6:7], s[2:3]
+; CHECK-NEXT:  .LBB0_9: ; %UnifiedUnreachableBlock
+; CHECK-NEXT:    ; divergent unreachable
+; CHECK-NEXT:  .LBB0_10: ; %Flow6
+; CHECK-NEXT:    s_or_b64 exec, exec, s[6:7]
+; CHECK-NEXT:    s_and_saveexec_b64 s[2:3], s[0:1]
+; CHECK-NEXT:    s_cbranch_execz .LBB0_12
+; CHECK-NEXT:  ; %bb.11: ; %if.end6.sink.split
+; CHECK-NEXT:    s_load_dwordx2 s[0:1], s[4:5], 0x8
+; CHECK-NEXT:    v_lshlrev_b32_e32 v0, 2, v0
+; CHECK-NEXT:    v_mov_b32_e32 v1, s10
+; CHECK-NEXT:    s_waitcnt lgkmcnt(0)
+; CHECK-NEXT:    global_store_dword v0, v1, s[0:1]
+; CHECK-NEXT:  .LBB0_12: ; %UnifiedReturnBlock
+; CHECK-NEXT:    s_endpgm
+; CHECK-NEXT:  .LBB0_13: ; %cond.false
+; CHECK-NEXT:    s_mov_b64 s[0:1], 0
+; CHECK-NEXT:    s_or_b64 s[2:3], s[2:3], exec
+; CHECK-NEXT:    s_trap 2
+; CHECK-NEXT:    s_and_saveexec_b64 s[6:7], s[2:3]
+; CHECK-NEXT:    s_cbranch_execnz .LBB0_9
+; CHECK-NEXT:    s_branch .LBB0_10
+; CHECK-NEXT:  .LBB0_14: ; %cond.false.i8
+; CHECK-NEXT:    s_mov_b64 s[2:3], -1
+; CHECK-NEXT:    s_mov_b64 s[0:1], 0
+; CHECK-NEXT:    s_trap 2
+; CHECK-NEXT:    s_branch .LBB0_4
+entry:
+  %tid = call i32 @llvm.amdgcn.workitem.id.x()
+  %cmp = icmp eq i32 %n, 256
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %cmp1 = icmp eq i32 %a, 0
+  br i1 %cmp1, label %if.end6.sink.split, label %cond.false
+
+cond.false:
+  call void @llvm.trap()
+  unreachable
+
+if.else:
+  %cmp2 = icmp ult i32 %tid, 10
+  br i1 %cmp2, label %if.then3, label %if.end6
+
+if.then3:
+  %cmp1.i7 = icmp eq i32 %a, 0
+  br i1 %cmp1.i7, label %if.end6.sink.split, label %cond.false.i8
+
+cond.false.i8:
+  call void @llvm.trap()
+  unreachable
+
+if.end6.sink.split:
+  %x1 = getelementptr inbounds i32, i32 addrspace(1)* %x, i32 %tid
+  store i32 %a, i32 addrspace(1)* %x1, align 4
+  br label %if.end6
+
+if.end6:
+  ret void
+}

diff --git a/llvm/test/CodeGen/AMDGPU/skip-if-dead.ll b/llvm/test/CodeGen/AMDGPU/skip-if-dead.ll
index ada6c1d..6d611d3 100644 (file)
--- a/llvm/test/CodeGen/AMDGPU/skip-if-dead.ll
+++ b/llvm/test/CodeGen/AMDGPU/skip-if-dead.ll
@@ -1292,40 +1292,45 @@ define amdgpu_ps void @no_skip_no_successors(float inreg %arg, float inreg %arg1
 ; SI-LABEL: no_skip_no_successors:
 ; SI:       ; %bb.0: ; %bb
 ; SI-NEXT:    v_cmp_nge_f32_e64 s[4:5], s1, 0
+; SI-NEXT:    s_mov_b64 s[2:3], exec
+; SI-NEXT:    s_mov_b64 s[0:1], -1
 ; SI-NEXT:    s_and_b64 vcc, exec, s[4:5]
 ; SI-NEXT:    s_cbranch_vccz .LBB12_3
-; SI-NEXT:  ; %bb.1: ; %bb6
-; SI-NEXT:    s_mov_b64 s[2:3], exec
+; SI-NEXT:  ; %bb.1: ; %Flow
+; SI-NEXT:    s_and_b64 vcc, exec, s[0:1]
+; SI-NEXT:    s_cbranch_vccnz .LBB12_4
+; SI-NEXT:  .LBB12_2: ; %UnifiedUnreachableBlock
+; SI-NEXT:  .LBB12_3: ; %bb3
+; SI-NEXT:    s_branch .LBB12_2
+; SI-NEXT:  .LBB12_4: ; %bb6
 ; SI-NEXT:    s_andn2_b64 s[2:3], s[2:3], exec
-; SI-NEXT:    s_cbranch_scc0 .LBB12_5
-; SI-NEXT:  ; %bb.2: ; %bb6
+; SI-NEXT:    s_cbranch_scc0 .LBB12_6
+; SI-NEXT:  ; %bb.5: ; %bb6
 ; SI-NEXT:    s_mov_b64 exec, 0
-; SI-NEXT:  .LBB12_3: ; %bb3
-; SI-NEXT:    v_mov_b32_e32 v0, 0x3e7ae148
-; SI-NEXT:    v_cmp_nge_f32_e32 vcc, s0, v0
-; SI-NEXT:    s_and_b64 vcc, exec, vcc
-; SI-NEXT:  ; %bb.4: ; %bb5
-; SI-NEXT:  .LBB12_5:
+; SI-NEXT:  .LBB12_6:
 ; SI-NEXT:    s_mov_b64 exec, 0
 ; SI-NEXT:    exp null off, off, off, off done vm
 ; SI-NEXT:    s_endpgm
 ;
 ; GFX10-WAVE64-LABEL: no_skip_no_successors:
 ; GFX10-WAVE64:       ; %bb.0: ; %bb
-; GFX10-WAVE64-NEXT:    v_cmp_nge_f32_e64 s[4:5], s1, 0
-; GFX10-WAVE64-NEXT:    s_and_b64 vcc, exec, s[4:5]
-; GFX10-WAVE64-NEXT:    s_cbranch_vccz .LBB12_3
-; GFX10-WAVE64-NEXT:  ; %bb.1: ; %bb6
+; GFX10-WAVE64-NEXT:    v_cmp_nge_f32_e64 s[0:1], s1, 0
 ; GFX10-WAVE64-NEXT:    s_mov_b64 s[2:3], exec
+; GFX10-WAVE64-NEXT:    s_and_b64 vcc, exec, s[0:1]
+; GFX10-WAVE64-NEXT:    s_mov_b64 s[0:1], -1
+; GFX10-WAVE64-NEXT:    s_cbranch_vccz .LBB12_3
+; GFX10-WAVE64-NEXT:  ; %bb.1: ; %Flow
+; GFX10-WAVE64-NEXT:    s_and_b64 vcc, exec, s[0:1]
+; GFX10-WAVE64-NEXT:    s_cbranch_vccnz .LBB12_4
+; GFX10-WAVE64-NEXT:  .LBB12_2: ; %UnifiedUnreachableBlock
+; GFX10-WAVE64-NEXT:  .LBB12_3: ; %bb3
+; GFX10-WAVE64-NEXT:    s_branch .LBB12_2
+; GFX10-WAVE64-NEXT:  .LBB12_4: ; %bb6
 ; GFX10-WAVE64-NEXT:    s_andn2_b64 s[2:3], s[2:3], exec
-; GFX10-WAVE64-NEXT:    s_cbranch_scc0 .LBB12_5
-; GFX10-WAVE64-NEXT:  ; %bb.2: ; %bb6
+; GFX10-WAVE64-NEXT:    s_cbranch_scc0 .LBB12_6
+; GFX10-WAVE64-NEXT:  ; %bb.5: ; %bb6
 ; GFX10-WAVE64-NEXT:    s_mov_b64 exec, 0
-; GFX10-WAVE64-NEXT:  .LBB12_3: ; %bb3
-; GFX10-WAVE64-NEXT:    v_cmp_nle_f32_e64 s[0:1], 0x3e7ae148, s0
-; GFX10-WAVE64-NEXT:    s_and_b64 vcc, exec, s[0:1]
-; GFX10-WAVE64-NEXT:  ; %bb.4: ; %bb5
-; GFX10-WAVE64-NEXT:  .LBB12_5:
+; GFX10-WAVE64-NEXT:  .LBB12_6:
 ; GFX10-WAVE64-NEXT:    s_mov_b64 exec, 0
 ; GFX10-WAVE64-NEXT:    exp null off, off, off, off done vm
 ; GFX10-WAVE64-NEXT:    s_endpgm
@@ -1333,42 +1338,46 @@ define amdgpu_ps void @no_skip_no_successors(float inreg %arg, float inreg %arg1
 ; GFX10-WAVE32-LABEL: no_skip_no_successors:
 ; GFX10-WAVE32:       ; %bb.0: ; %bb
 ; GFX10-WAVE32-NEXT:    v_cmp_nge_f32_e64 s1, s1, 0
+; GFX10-WAVE32-NEXT:    s_mov_b32 s0, exec_lo
 ; GFX10-WAVE32-NEXT:    s_and_b32 vcc_lo, exec_lo, s1
+; GFX10-WAVE32-NEXT:    s_mov_b32 s1, -1
 ; GFX10-WAVE32-NEXT:    s_cbranch_vccz .LBB12_3
-; GFX10-WAVE32-NEXT:  ; %bb.1: ; %bb6
-; GFX10-WAVE32-NEXT:    s_mov_b32 s2, exec_lo
-; GFX10-WAVE32-NEXT:    s_andn2_b32 s2, s2, exec_lo
-; GFX10-WAVE32-NEXT:    s_cbranch_scc0 .LBB12_5
-; GFX10-WAVE32-NEXT:  ; %bb.2: ; %bb6
-; GFX10-WAVE32-NEXT:    s_mov_b32 exec_lo, 0
+; GFX10-WAVE32-NEXT:  ; %bb.1: ; %Flow
+; GFX10-WAVE32-NEXT:    s_and_b32 vcc_lo, exec_lo, s1
+; GFX10-WAVE32-NEXT:    s_cbranch_vccnz .LBB12_4
+; GFX10-WAVE32-NEXT:  .LBB12_2: ; %UnifiedUnreachableBlock
 ; GFX10-WAVE32-NEXT:  .LBB12_3: ; %bb3
-; GFX10-WAVE32-NEXT:    v_cmp_nle_f32_e64 s0, 0x3e7ae148, s0
-; GFX10-WAVE32-NEXT:    s_and_b32 vcc_lo, exec_lo, s0
-; GFX10-WAVE32-NEXT:  ; %bb.4: ; %bb5
-; GFX10-WAVE32-NEXT:  .LBB12_5:
+; GFX10-WAVE32-NEXT:    s_branch .LBB12_2
+; GFX10-WAVE32-NEXT:  .LBB12_4: ; %bb6
+; GFX10-WAVE32-NEXT:    s_andn2_b32 s0, s0, exec_lo
+; GFX10-WAVE32-NEXT:    s_cbranch_scc0 .LBB12_6
+; GFX10-WAVE32-NEXT:  ; %bb.5: ; %bb6
+; GFX10-WAVE32-NEXT:    s_mov_b32 exec_lo, 0
+; GFX10-WAVE32-NEXT:  .LBB12_6:
 ; GFX10-WAVE32-NEXT:    s_mov_b32 exec_lo, 0
 ; GFX10-WAVE32-NEXT:    exp null off, off, off, off done vm
 ; GFX10-WAVE32-NEXT:    s_endpgm
 ;
 ; GFX11-LABEL: no_skip_no_successors:
 ; GFX11:       ; %bb.0: ; %bb
-; GFX11-NEXT:    v_cmp_nge_f32_e64 s[4:5], s1, 0
+; GFX11-NEXT:    v_cmp_nge_f32_e64 s[0:1], s1, 0
+; GFX11-NEXT:    s_mov_b64 s[2:3], exec
 ; GFX11-NEXT:    s_delay_alu instid0(VALU_DEP_1)
-; GFX11-NEXT:    s_and_b64 vcc, exec, s[4:5]
+; GFX11-NEXT:    s_and_b64 vcc, exec, s[0:1]
+; GFX11-NEXT:    s_mov_b64 s[0:1], -1
 ; GFX11-NEXT:    s_cbranch_vccz .LBB12_3
-; GFX11-NEXT:  ; %bb.1: ; %bb6
-; GFX11-NEXT:    s_mov_b64 s[2:3], exec
-; GFX11-NEXT:    s_delay_alu instid0(SALU_CYCLE_1)
+; GFX11-NEXT:  ; %bb.1: ; %Flow
+; GFX11-NEXT:    s_and_b64 vcc, exec, s[0:1]
+; GFX11-NEXT:    s_cbranch_vccnz .LBB12_4
+; GFX11-NEXT:  .LBB12_2: ; %UnifiedUnreachableBlock
+; GFX11-NEXT:  .LBB12_3: ; %bb3
+; GFX11-NEXT:    s_branch .LBB12_2
+; GFX11-NEXT:  .LBB12_4: ; %bb6
 ; GFX11-NEXT:    s_and_not1_b64 s[2:3], s[2:3], exec
-; GFX11-NEXT:    s_cbranch_scc0 .LBB12_5
-; GFX11-NEXT:  ; %bb.2: ; %bb6
+; GFX11-NEXT:    s_cbranch_scc0 .LBB12_6
+; GFX11-NEXT:  ; %bb.5: ; %bb6
 ; GFX11-NEXT:    s_mov_b64 exec, 0
-; GFX11-NEXT:  .LBB12_3: ; %bb3
-; GFX11-NEXT:    v_cmp_nle_f32_e64 s[0:1], 0x3e7ae148, s0
-; GFX11-NEXT:    s_delay_alu instid0(VALU_DEP_1)
-; GFX11-NEXT:    s_and_b64 vcc, exec, s[0:1]
-; GFX11-NEXT:  ; %bb.4: ; %bb5
-; GFX11-NEXT:  .LBB12_5:
+; GFX11-NEXT:  .LBB12_6:
 ; GFX11-NEXT:    s_mov_b64 exec, 0
 ; GFX11-NEXT:    exp mrt0 off, off, off, off done
 ; GFX11-NEXT:    s_endpgm

diff --git a/llvm/test/CodeGen/AMDGPU/switch-default-block-unreachable.ll b/llvm/test/CodeGen/AMDGPU/switch-default-block-unreachable.ll
index 13c4dc8..1a0d90c 100644 (file)
--- a/llvm/test/CodeGen/AMDGPU/switch-default-block-unreachable.ll
+++ b/llvm/test/CodeGen/AMDGPU/switch-default-block-unreachable.ll
@@ -8,6 +8,7 @@ define void @test() #1 {
   ;
   ; GCN-LABEL: name: test
   ; GCN: bb.{{[0-9]+}}.entry:
+  ; GCN: bb.{{[0-9]+}}.Flow1:
   ; GCN: bb.{{[0-9]+}}.entry.true.blk:
   ; GCN: bb.{{[0-9]+}}.entry.false.blk:
   ; GCN: bb.{{[0-9]+}}.switch.blk:
@@ -17,7 +18,8 @@ define void @test() #1 {
   ; GCN-NOT: bb.{{[0-9]+}}.unreach.blk:
   ; GCN-NOT: PHI
 
-  ; GCN: bb.{{[0-9]+}}.exit:
+  ; GCN: bb.{{[0-9]+}}.Flow:
+  ; GCN: bb.{{[0-9]+}}.UnifiedReturnBlock:
   entry:
     %idx = tail call i32 @llvm.amdgcn.workitem.id.x() #0
     br i1 undef, label %entry.true.blk, label %entry.false.blk