; XFAIL: *
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -mtriple=amdgcn-amd-amdhsa -S -structurizecfg %s | FileCheck %s
; StructurizeCFG::orderNodes used an arbitrary and nonsensical sorting
; function which broke the basic backedge identification algorithm. It
; would use RPO order, but then do a weird partial sort by the loop
; depth assuming blocks are sorted by loop. However a block can appear
; in between blocks of a loop that is not part of a loop, breaking the
; assumption of the sort.
;
; The collectInfos must be done in RPO order. The actual
; structurization order I think is less important, but unless the loop
; headers are identified in RPO order, it finds the wrong set of back
; edges.
define amdgpu_kernel void @loop_backedge_misidentified(ptr addrspace(1) %arg0) #0 {
; CHECK-LABEL: @loop_backedge_misidentified(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP:%.*]] = load volatile <2 x i32>, ptr addrspace(1) undef, align 16
; CHECK-NEXT: [[LOAD1:%.*]] = load volatile <2 x float>, ptr addrspace(1) undef
; CHECK-NEXT: [[TID:%.*]] = call i32 @llvm.amdgcn.workitem.id.x()
; CHECK-NEXT: [[GEP:%.*]] = getelementptr inbounds i32, ptr addrspace(1) [[ARG0:%.*]], i32 [[TID]]
; CHECK-NEXT: [[I_INITIAL:%.*]] = load volatile i32, ptr addrspace(1) [[GEP]], align 4
; CHECK-NEXT: br label [[LOOP_HEADER:%.*]]
; CHECK: LOOP.HEADER:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_INITIAL]], [[ENTRY:%.*]] ], [ [[TMP10:%.*]], [[FLOW4:%.*]] ]
; CHECK-NEXT: call void asm sideeffect "s_nop 0x100b
; CHECK-NEXT: [[TMP12:%.*]] = zext i32 [[I]] to i64
; CHECK-NEXT: [[TMP13:%.*]] = getelementptr inbounds <4 x i32>, ptr addrspace(1) null, i64 [[TMP12]]
; CHECK-NEXT: [[TMP14:%.*]] = load <4 x i32>, ptr addrspace(1) [[TMP13]], align 16
; CHECK-NEXT: [[TMP15:%.*]] = extractelement <4 x i32> [[TMP14]], i64 0
; CHECK-NEXT: [[TMP16:%.*]] = and i32 [[TMP15]], 65535
; CHECK-NEXT: [[TMP17:%.*]] = icmp eq i32 [[TMP16]], 1
; CHECK-NEXT: [[TMP0:%.*]] = xor i1 [[TMP17]], true
; CHECK-NEXT: br i1 [[TMP0]], label [[BB62:%.*]], label [[FLOW:%.*]]
; CHECK: Flow2:
; CHECK-NEXT: br label [[FLOW]]
; CHECK: bb18:
; CHECK-NEXT: [[TMP19:%.*]] = extractelement <2 x i32> [[TMP]], i64 0
; CHECK-NEXT: [[TMP22:%.*]] = lshr i32 [[TMP19]], 16
; CHECK-NEXT: [[TMP24:%.*]] = urem i32 [[TMP22]], 52
; CHECK-NEXT: [[TMP25:%.*]] = mul nuw nsw i32 [[TMP24]], 52
; CHECK-NEXT: br label [[INNER_LOOP:%.*]]
; CHECK: Flow3:
; CHECK-NEXT: [[TMP1:%.*]] = phi i32 [ [[TMP59:%.*]], [[INNER_LOOP_BREAK:%.*]] ], [ [[TMP7:%.*]], [[FLOW]] ]
; CHECK-NEXT: [[TMP2:%.*]] = phi i1 [ true, [[INNER_LOOP_BREAK]] ], [ [[TMP8:%.*]], [[FLOW]] ]
; CHECK-NEXT: br i1 [[TMP2]], label [[END_ELSE_BLOCK:%.*]], label [[FLOW4]]
; CHECK: INNER_LOOP:
; CHECK-NEXT: [[INNER_LOOP_J:%.*]] = phi i32 [ [[INNER_LOOP_J_INC:%.*]], [[INNER_LOOP]] ], [ [[TMP25]], [[BB18:%.*]] ]
; CHECK-NEXT: call void asm sideeffect "
; CHECK-NEXT: [[INNER_LOOP_J_INC]] = add nsw i32 [[INNER_LOOP_J]], 1
; CHECK-NEXT: [[INNER_LOOP_CMP:%.*]] = icmp eq i32 [[INNER_LOOP_J]], 0
; CHECK-NEXT: br i1 [[INNER_LOOP_CMP]], label [[INNER_LOOP_BREAK]], label [[INNER_LOOP]]
; CHECK: INNER_LOOP_BREAK:
; CHECK-NEXT: [[TMP59]] = extractelement <4 x i32> [[TMP14]], i64 2
; CHECK-NEXT: call void asm sideeffect "s_nop 23 ", "~{memory}"() #0
; CHECK-NEXT: br label [[FLOW3:%.*]]
; CHECK: bb62:
; CHECK-NEXT: [[LOAD13:%.*]] = icmp ult i32 [[TMP16]], 271
; CHECK-NEXT: [[TMP3:%.*]] = xor i1 [[LOAD13]], true
; CHECK-NEXT: br i1 [[TMP3]], label [[INCREMENT_I:%.*]], label [[FLOW1:%.*]]
; CHECK: Flow1:
; CHECK-NEXT: [[TMP4:%.*]] = phi i32 [ [[INC_I:%.*]], [[INCREMENT_I]] ], [ undef, [[BB62]] ]
; CHECK-NEXT: [[TMP5:%.*]] = phi i1 [ true, [[INCREMENT_I]] ], [ false, [[BB62]] ]
; CHECK-NEXT: [[TMP6:%.*]] = phi i1 [ false, [[INCREMENT_I]] ], [ true, [[BB62]] ]
; CHECK-NEXT: br i1 [[TMP6]], label [[BB64:%.*]], label [[FLOW2:%.*]]
; CHECK: bb64:
; CHECK-NEXT: call void asm sideeffect "s_nop 42", "~{memory}"() #0
; CHECK-NEXT: br label [[FLOW2]]
; CHECK: Flow:
; CHECK-NEXT: [[TMP7]] = phi i32 [ [[TMP4]], [[FLOW2]] ], [ undef, [[LOOP_HEADER]] ]
; CHECK-NEXT: [[TMP8]] = phi i1 [ [[TMP5]], [[FLOW2]] ], [ false, [[LOOP_HEADER]] ]
; CHECK-NEXT: [[TMP9:%.*]] = phi i1 [ false, [[FLOW2]] ], [ true, [[LOOP_HEADER]] ]
; CHECK-NEXT: br i1 [[TMP9]], label [[BB18]], label [[FLOW3]]
; CHECK: INCREMENT_I:
; CHECK-NEXT: [[INC_I]] = add i32 [[I]], 1
; CHECK-NEXT: call void asm sideeffect "s_nop 0x1336
; CHECK-NEXT: br label [[FLOW1]]
; CHECK: END_ELSE_BLOCK:
; CHECK-NEXT: [[I_FINAL:%.*]] = phi i32 [ [[TMP1]], [[FLOW3]] ]
; CHECK-NEXT: call void asm sideeffect "s_nop 0x1337
; CHECK-NEXT: [[CMP_END_ELSE_BLOCK:%.*]] = icmp eq i32 [[I_FINAL]], -1
; CHECK-NEXT: br label [[FLOW4]]
; CHECK: Flow4:
; CHECK-NEXT: [[TMP10]] = phi i32 [ [[I_FINAL]], [[END_ELSE_BLOCK]] ], [ undef, [[FLOW3]] ]
; CHECK-NEXT: [[TMP11:%.*]] = phi i1 [ [[CMP_END_ELSE_BLOCK]], [[END_ELSE_BLOCK]] ], [ true, [[FLOW3]] ]
; CHECK-NEXT: br i1 [[TMP11]], label [[RETURN:%.*]], label [[LOOP_HEADER]]
; CHECK: RETURN:
; CHECK-NEXT: call void asm sideeffect "s_nop 0x99
; CHECK-NEXT: store volatile <2 x float> [[LOAD1]], ptr addrspace(1) undef, align 8
; CHECK-NEXT: ret void
;
entry:
%tmp = load volatile <2 x i32>, ptr addrspace(1) undef, align 16
%load1 = load volatile <2 x float>, ptr addrspace(1) undef
%tid = call i32 @llvm.amdgcn.workitem.id.x()
%gep = getelementptr inbounds i32, ptr addrspace(1) %arg0, i32 %tid
%i.initial = load volatile i32, ptr addrspace(1) %gep, align 4
br label %LOOP.HEADER
LOOP.HEADER:
%i = phi i32 [ %i.final, %END_ELSE_BLOCK ], [ %i.initial, %entry ]
call void asm sideeffect "s_nop 0x100b ; loop $0 ", "r,~{memory}"(i32 %i) #0
%tmp12 = zext i32 %i to i64
%tmp13 = getelementptr inbounds <4 x i32>, ptr addrspace(1) null, i64 %tmp12
%tmp14 = load <4 x i32>, ptr addrspace(1) %tmp13, align 16
%tmp15 = extractelement <4 x i32> %tmp14, i64 0
%tmp16 = and i32 %tmp15, 65535
%tmp17 = icmp eq i32 %tmp16, 1
br i1 %tmp17, label %bb18, label %bb62
bb18:
%tmp19 = extractelement <2 x i32> %tmp, i64 0
%tmp22 = lshr i32 %tmp19, 16
%tmp24 = urem i32 %tmp22, 52
%tmp25 = mul nuw nsw i32 %tmp24, 52
br label %INNER_LOOP
INNER_LOOP:
%inner.loop.j = phi i32 [ %tmp25, %bb18 ], [ %inner.loop.j.inc, %INNER_LOOP ]
call void asm sideeffect "; inner loop body", ""() #0
%inner.loop.j.inc = add nsw i32 %inner.loop.j, 1
%inner.loop.cmp = icmp eq i32 %inner.loop.j, 0
br i1 %inner.loop.cmp, label %INNER_LOOP_BREAK, label %INNER_LOOP
INNER_LOOP_BREAK:
%tmp59 = extractelement <4 x i32> %tmp14, i64 2
call void asm sideeffect "s_nop 23 ", "~{memory}"() #0
br label %END_ELSE_BLOCK
bb62:
%load13 = icmp ult i32 %tmp16, 271
br i1 %load13, label %bb64, label %INCREMENT_I
bb64:
call void asm sideeffect "s_nop 42", "~{memory}"() #0
br label %RETURN
INCREMENT_I:
%inc.i = add i32 %i, 1
call void asm sideeffect "s_nop 0x1336 ; increment $0", "v,~{memory}"(i32 %inc.i) #0
br label %END_ELSE_BLOCK
END_ELSE_BLOCK:
%i.final = phi i32 [ %tmp59, %INNER_LOOP_BREAK ], [ %inc.i, %INCREMENT_I ]
call void asm sideeffect "s_nop 0x1337 ; end else block $0", "v,~{memory}"(i32 %i.final) #0
%cmp.end.else.block = icmp eq i32 %i.final, -1
br i1 %cmp.end.else.block, label %RETURN, label %LOOP.HEADER
RETURN:
call void asm sideeffect "s_nop 0x99 ; ClosureEval return", "~{memory}"() #0
store volatile <2 x float> %load1, ptr addrspace(1) undef, align 8
ret void
}
; The same function, except break to return block goes directly to the
; return, which managed to hide the bug.
define amdgpu_kernel void @loop_backedge_misidentified_alt(ptr addrspace(1) %arg0) #0 {
entry:
%tmp = load volatile <2 x i32>, ptr addrspace(1) undef, align 16
%load1 = load volatile <2 x float>, ptr addrspace(1) undef
%tid = call i32 @llvm.amdgcn.workitem.id.x()
%gep = getelementptr inbounds i32, ptr addrspace(1) %arg0, i32 %tid
%i.initial = load volatile i32, ptr addrspace(1) %gep, align 4
br label %LOOP.HEADER
LOOP.HEADER:
%i = phi i32 [ %i.final, %END_ELSE_BLOCK ], [ %i.initial, %entry ]
call void asm sideeffect "s_nop 0x100b ; loop $0 ", "r,~{memory}"(i32 %i) #0
%tmp12 = zext i32 %i to i64
%tmp13 = getelementptr inbounds <4 x i32>, ptr addrspace(1) null, i64 %tmp12
%tmp14 = load <4 x i32>, ptr addrspace(1) %tmp13, align 16
%tmp15 = extractelement <4 x i32> %tmp14, i64 0
%tmp16 = and i32 %tmp15, 65535
%tmp17 = icmp eq i32 %tmp16, 1
br i1 %tmp17, label %bb18, label %bb62
bb18:
%tmp19 = extractelement <2 x i32> %tmp, i64 0
%tmp22 = lshr i32 %tmp19, 16
%tmp24 = urem i32 %tmp22, 52
%tmp25 = mul nuw nsw i32 %tmp24, 52
br label %INNER_LOOP
INNER_LOOP:
%inner.loop.j = phi i32 [ %tmp25, %bb18 ], [ %inner.loop.j.inc, %INNER_LOOP ]
call void asm sideeffect "; inner loop body", ""() #0
%inner.loop.j.inc = add nsw i32 %inner.loop.j, 1
%inner.loop.cmp = icmp eq i32 %inner.loop.j, 0
br i1 %inner.loop.cmp, label %INNER_LOOP_BREAK, label %INNER_LOOP
INNER_LOOP_BREAK:
%tmp59 = extractelement <4 x i32> %tmp14, i64 2
call void asm sideeffect "s_nop 23 ", "~{memory}"() #0
br label %END_ELSE_BLOCK
bb62:
%load13 = icmp ult i32 %tmp16, 271
;br i1 %load13, label %bb64, label %INCREMENT_I
; branching directly to the return avoids the bug
br i1 %load13, label %RETURN, label %INCREMENT_I
bb64:
call void asm sideeffect "s_nop 42", "~{memory}"() #0
br label %RETURN
INCREMENT_I:
%inc.i = add i32 %i, 1
call void asm sideeffect "s_nop 0x1336 ; increment $0", "v,~{memory}"(i32 %inc.i) #0
br label %END_ELSE_BLOCK
END_ELSE_BLOCK:
%i.final = phi i32 [ %tmp59, %INNER_LOOP_BREAK ], [ %inc.i, %INCREMENT_I ]
call void asm sideeffect "s_nop 0x1337 ; end else block $0", "v,~{memory}"(i32 %i.final) #0
%cmp.end.else.block = icmp eq i32 %i.final, -1
br i1 %cmp.end.else.block, label %RETURN, label %LOOP.HEADER
RETURN:
call void asm sideeffect "s_nop 0x99 ; ClosureEval return", "~{memory}"() #0
store volatile <2 x float> %load1, ptr addrspace(1) undef, align 8
ret void
}
declare i32 @llvm.amdgcn.workitem.id.x() #1
attributes #0 = { convergent nounwind }
attributes #1 = { convergent nounwind readnone }
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