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; RUN: opt < %s -disable-output "-passes=print<ddg>" 2>&1 | FileCheck %s
; CHECK-LABEL: 'DDG' for loop 'test1.for.body':
; CHECK: Node Address:[[N1:0x[0-9a-f]*]]:pi-block
; CHECK-NEXT:--- start of nodes in pi-block ---
; CHECK: Node Address:[[N2:0x[0-9a-f]*]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %i.02 = phi i64 [ %inc, %test1.for.body ], [ 1, %test1.for.body.preheader ]
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N3:0x[0-9a-f]*]]
; CHECK: Node Address:[[N3]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %inc = add i64 %i.02, 1
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N2]]
; CHECK-NEXT:--- end of nodes in pi-block ---
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N4:0x[0-9a-f]*]]
; CHECK-NEXT: [def-use] to [[N5:0x[0-9a-f]*]]
; CHECK-NEXT: [def-use] to [[N6:0x[0-9a-f]*]]
; CHECK-NEXT: [def-use] to [[N7:0x[0-9a-f]*]]
; CHECK: Node Address:[[N7]]:multi-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %cmp = icmp ult i64 %inc, %sub
; CHECK-NEXT: br i1 %cmp, label %test1.for.body, label %for.end.loopexit
; CHECK-NEXT: Edges:none!
; CHECK: Node Address:[[N6]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %arrayidx3 = getelementptr inbounds float, float* %a, i64 %i.02
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N8:0x[0-9a-f]*]]
; CHECK: Node Address:[[N5]]:multi-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %sub1 = add i64 %i.02, -1
; CHECK-NEXT: %arrayidx2 = getelementptr inbounds float, float* %a, i64 %sub1
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N8]]
; CHECK: Node Address:[[N4]]:multi-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %arrayidx = getelementptr inbounds float, float* %b, i64 %i.02
; CHECK-NEXT: %0 = load float, float* %arrayidx, align 4
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N8]]
; CHECK: Node Address:[[N8]]:pi-block
; CHECK-NEXT: --- start of nodes in pi-block ---
; CHECK: Node Address:[[N9:0x[0-9a-f]*]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %1 = load float, float* %arrayidx2, align 4
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N10:0x[0-9a-f]*]]
; CHECK: Node Address:[[N10]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %add = fadd float %0, %1
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N11:0x[0-9a-f]*]]
; CHECK: Node Address:[[N11]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: store float %add, float* %arrayidx3, align 4
; CHECK-NEXT: Edges:
; CHECK-NEXT: [memory] to [[N9]]
; CHECK-NEXT:--- end of nodes in pi-block ---
; CHECK-NEXT: Edges:none!
;; Loop-carried dependence requiring edge-reversal to expose a cycle
;; in the graph.
;; void test(unsigned long n, float * restrict a, float * restrict b) {
;; for (unsigned long i = 1; i < n-1; i++)
;; a[i] = b[i] + a[i-1];
;; }
define void @test1(i64 %n, float* noalias %a, float* noalias %b) {
entry:
%sub = add i64 %n, -1
%cmp1 = icmp ult i64 1, %sub
br i1 %cmp1, label %test1.for.body, label %for.end
test1.for.body: ; preds = %entry, %test1.for.body
%i.02 = phi i64 [ %inc, %test1.for.body ], [ 1, %entry ]
%arrayidx = getelementptr inbounds float, float* %b, i64 %i.02
%0 = load float, float* %arrayidx, align 4
%sub1 = add i64 %i.02, -1
%arrayidx2 = getelementptr inbounds float, float* %a, i64 %sub1
%1 = load float, float* %arrayidx2, align 4
%add = fadd float %0, %1
%arrayidx3 = getelementptr inbounds float, float* %a, i64 %i.02
store float %add, float* %arrayidx3, align 4
%inc = add i64 %i.02, 1
%cmp = icmp ult i64 %inc, %sub
br i1 %cmp, label %test1.for.body, label %for.end
for.end: ; preds = %test1.for.body, %entry
ret void
}
; CHECK-LABEL: 'DDG' for loop 'test2.for.body':
; CHECK: Node Address:[[N1:0x[0-9a-f]*]]:pi-block
; CHECK-NEXT:--- start of nodes in pi-block ---
; CHECK: Node Address:[[N2:0x[0-9a-f]*]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %i.02 = phi i64 [ %inc, %test2.for.body ], [ 1, %test2.for.body.preheader ]
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N3:0x[0-9a-f]*]]
; CHECK: Node Address:[[N3]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %inc = add i64 %i.02, 1
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N2]]
; CHECK-NEXT:--- end of nodes in pi-block ---
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N4:0x[0-9a-f]*]]
; CHECK-NEXT: [def-use] to [[N5:0x[0-9a-f]*]]
; CHECK-NEXT: [def-use] to [[N6:0x[0-9a-f]*]]
; CHECK-NEXT: [def-use] to [[N7:0x[0-9a-f]*]]
; CHECK: Node Address:[[N7]]:multi-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %cmp = icmp ult i64 %inc, %sub
; CHECK-NEXT: br i1 %cmp, label %test2.for.body, label %for.end.loopexit
; CHECK-NEXT: Edges:none!
; CHECK: Node Address:[[N6]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %arrayidx3 = getelementptr inbounds float, float* %a, i64 %i.02
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N8:0x[0-9a-f]*]]
; CHECK: Node Address:[[N5]]:multi-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %add1 = add i64 %i.02, 1
; CHECK-NEXT: %arrayidx2 = getelementptr inbounds float, float* %a, i64 %add1
; CHECK-NEXT: %1 = load float, float* %arrayidx2, align 4
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N9:0x[0-9a-f]*]]
; CHECK-NEXT: [memory] to [[N8]]
; CHECK: Node Address:[[N4]]:multi-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %arrayidx = getelementptr inbounds float, float* %b, i64 %i.02
; CHECK-NEXT: %0 = load float, float* %arrayidx, align 4
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N9]]
; CHECK: Node Address:[[N9]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: %add = fadd float %0, %1
; CHECK-NEXT: Edges:
; CHECK-NEXT: [def-use] to [[N8]]
; CHECK: Node Address:[[N8]]:single-instruction
; CHECK-NEXT: Instructions:
; CHECK-NEXT: store float %add, float* %arrayidx3, align 4
; CHECK-NEXT: Edges:none!
;; Forward loop-carried dependence *not* causing a cycle.
;; void test2(unsigned long n, float * restrict a, float * restrict b) {
;; for (unsigned long i = 1; i < n-1; i++)
;; a[i] = b[i] + a[i+1];
;; }
define void @test2(i64 %n, float* noalias %a, float* noalias %b) {
entry:
%sub = add i64 %n, -1
%cmp1 = icmp ult i64 1, %sub
br i1 %cmp1, label %test2.for.body, label %for.end
test2.for.body: ; preds = %entry, %test2.for.body
%i.02 = phi i64 [ %inc, %test2.for.body ], [ 1, %entry ]
%arrayidx = getelementptr inbounds float, float* %b, i64 %i.02
%0 = load float, float* %arrayidx, align 4
%add1 = add i64 %i.02, 1
%arrayidx2 = getelementptr inbounds float, float* %a, i64 %add1
%1 = load float, float* %arrayidx2, align 4
%add = fadd float %0, %1
%arrayidx3 = getelementptr inbounds float, float* %a, i64 %i.02
store float %add, float* %arrayidx3, align 4
%inc = add i64 %i.02, 1
%cmp = icmp ult i64 %inc, %sub
br i1 %cmp, label %test2.for.body, label %for.end
for.end: ; preds = %test2.for.body, %entry
ret void
}
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