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; RUN: opt < %s -indvars -S | FileCheck %s
; This tests that the IV is not recomputed outside of the loop when it is known
; to be computed by the loop and used in the loop any way. In the example below
; although a's value can be computed outside of the loop, there is no benefit
; in doing so as it has to be computed by the loop anyway.
;
; extern void func(unsigned val);
;
; void test(unsigned m)
; {
; unsigned a = 0;
;
; for (int i=0; i<186; i++) {
; a += m;
; func(a);
; }
;
; func(a);
; }
declare void @func(i32)
; CHECK-LABEL: @test(
define void @test(i32 %m) nounwind uwtable {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%i.06 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%a.05 = phi i32 [ 0, %entry ], [ %add, %for.body ]
%add = add i32 %a.05, %m
; CHECK: tail call void @func(i32 %add)
tail call void @func(i32 %add)
%inc = add nsw i32 %i.06, 1
%exitcond = icmp eq i32 %inc, 186
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
; CHECK: for.end:
; CHECK-NOT: mul i32 %m, 186
; CHECK:%add.lcssa = phi i32 [ %add, %for.body ]
; CHECK-NEXT: tail call void @func(i32 %add.lcssa)
tail call void @func(i32 %add)
ret void
}
; CHECK-LABEL: @test2(
define i32 @test2(i32 %m) nounwind uwtable {
entry:
br label %for.body
for.body: ; preds = %for.body, %entry
%i.06 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%a.05 = phi i32 [ 0, %entry ], [ %add, %for.body ]
%add = add i32 %a.05, %m
; CHECK: tail call void @func(i32 %add)
tail call void @func(i32 %add)
%inc = add nsw i32 %i.06, 1
%exitcond = icmp eq i32 %inc, 186
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body
; CHECK: for.end:
; CHECK-NOT: mul i32 %m, 186
; CHECK:%add.lcssa = phi i32 [ %add, %for.body ]
; CHECK-NEXT: ret i32 %add.lcssa
ret i32 %add
}
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