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; RUN: opt -mtriple amdgcn-unknown-amdhsa -passes='print<divergence>' -disable-output %s 2>&1 | FileCheck %s
; temporal-divergent use of value carried by divergent loop
define amdgpu_kernel void @temporal_diverge(i32 %n, i32 %a, i32 %b) #0 {
; CHECK-LABEL: Divergence Analysis' for function 'temporal_diverge':
; CHECK-NOT: DIVERGENT: %uni.
; CHECK-NOT: DIVERGENT: br i1 %uni.
entry:
%tid = call i32 @llvm.amdgcn.workitem.id.x()
%uni.cond = icmp slt i32 %a, 0
br label %H
H:
%uni.merge.h = phi i32 [ 0, %entry ], [ %uni.inc, %H ]
%uni.inc = add i32 %uni.merge.h, 1
%div.exitx = icmp slt i32 %tid, 0
br i1 %div.exitx, label %X, label %H ; divergent branch
; CHECK: DIVERGENT: %div.exitx =
; CHECK: DIVERGENT: br i1 %div.exitx,
X:
%div.user = add i32 %uni.inc, 5
ret void
}
; temporal-divergent use of value carried by divergent loop inside a top-level loop
define amdgpu_kernel void @temporal_diverge_inloop(i32 %n, i32 %a, i32 %b) #0 {
; CHECK-LABEL: Divergence Analysis' for function 'temporal_diverge_inloop':
; CHECK-NOT: DIVERGENT: %uni.
; CHECK-NOT: DIVERGENT: br i1 %uni.
entry:
%tid = call i32 @llvm.amdgcn.workitem.id.x()
%uni.cond = icmp slt i32 %a, 0
br label %G
G:
br label %H
H:
%uni.merge.h = phi i32 [ 0, %G ], [ %uni.inc, %H ]
%uni.inc = add i32 %uni.merge.h, 1
%div.exitx = icmp slt i32 %tid, 0
br i1 %div.exitx, label %X, label %H ; divergent branch
; CHECK: DIVERGENT: %div.exitx =
; CHECK: DIVERGENT: br i1 %div.exitx,
X:
%div.user = add i32 %uni.inc, 5
br i1 %uni.cond, label %G, label %Y
Y:
%div.alsouser = add i32 %uni.inc, 5
ret void
}
; temporal-uniform use of a valud, definition and users are carried by a surrounding divergent loop
define amdgpu_kernel void @temporal_uniform_indivloop(i32 %n, i32 %a, i32 %b) #0 {
; CHECK-LABEL: Divergence Analysis' for function 'temporal_uniform_indivloop':
; CHECK-NOT: DIVERGENT: %uni.
; CHECK-NOT: DIVERGENT: br i1 %uni.
entry:
%tid = call i32 @llvm.amdgcn.workitem.id.x()
%uni.cond = icmp slt i32 %a, 0
br label %G
G:
br label %H
H:
%uni.merge.h = phi i32 [ 0, %G ], [ %uni.inc, %H ]
%uni.inc = add i32 %uni.merge.h, 1
br i1 %uni.cond, label %X, label %H ; divergent branch
X:
%uni.user = add i32 %uni.inc, 5
%div.exity = icmp slt i32 %tid, 0
; CHECK: DIVERGENT: %div.exity =
br i1 %div.exity, label %G, label %Y
; CHECK: DIVERGENT: br i1 %div.exity,
Y:
%div.alsouser = add i32 %uni.inc, 5
ret void
}
; temporal-divergent use of value carried by divergent loop, user is inside sibling loop
define amdgpu_kernel void @temporal_diverge_loopuser(i32 %n, i32 %a, i32 %b) #0 {
; CHECK-LABEL: Divergence Analysis' for function 'temporal_diverge_loopuser':
; CHECK-NOT: DIVERGENT: %uni.
; CHECK-NOT: DIVERGENT: br i1 %uni.
entry:
%tid = call i32 @llvm.amdgcn.workitem.id.x()
%uni.cond = icmp slt i32 %a, 0
br label %H
H:
%uni.merge.h = phi i32 [ 0, %entry ], [ %uni.inc, %H ]
%uni.inc = add i32 %uni.merge.h, 1
%div.exitx = icmp slt i32 %tid, 0
br i1 %div.exitx, label %X, label %H ; divergent branch
; CHECK: DIVERGENT: %div.exitx =
; CHECK: DIVERGENT: br i1 %div.exitx,
X:
br label %G
G:
%div.user = add i32 %uni.inc, 5
br i1 %uni.cond, label %G, label %Y
Y:
ret void
}
; temporal-divergent use of value carried by divergent loop, user is inside sibling loop, defs and use are carried by a uniform loop
define amdgpu_kernel void @temporal_diverge_loopuser_nested(i32 %n, i32 %a, i32 %b) #0 {
; CHECK-LABEL: Divergence Analysis' for function 'temporal_diverge_loopuser_nested':
; CHECK-NOT: DIVERGENT: %uni.
; CHECK-NOT: DIVERGENT: br i1 %uni.
entry:
%tid = call i32 @llvm.amdgcn.workitem.id.x()
%uni.cond = icmp slt i32 %a, 0
br label %H
H:
%uni.merge.h = phi i32 [ 0, %entry ], [ %uni.inc, %H ]
%uni.inc = add i32 %uni.merge.h, 1
%div.exitx = icmp slt i32 %tid, 0
br i1 %div.exitx, label %X, label %H ; divergent branch
; CHECK: DIVERGENT: %div.exitx =
; CHECK: DIVERGENT: br i1 %div.exitx,
X:
br label %G
G:
%div.user = add i32 %uni.inc, 5
br i1 %uni.cond, label %G, label %Y
Y:
ret void
}
declare i32 @llvm.amdgcn.workitem.id.x() #0
attributes #0 = { nounwind readnone }
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