37 lines
1.5 KiB
LLVM
37 lines
1.5 KiB
LLVM
|
; RUN: opt < %s -analyze -enable-new-pm=0 -scalar-evolution | FileCheck %s
|
||
|
|
; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck %s
|
||
|
|
|
||
|
|
; CHECK: Determining loop execution counts for: @test
|
||
|
|
; CHECK: Loop %for.body: backedge-taken count is ((-2 + %len) /u 2)
|
||
|
|
; CHECK: Loop %for.body: max backedge-taken count is 1073741823
|
||
|
|
|
||
|
|
define zeroext i16 @test(i16* nocapture %p, i32 %len) nounwind readonly {
|
||
|
|
entry:
|
||
|
|
%cmp2 = icmp sgt i32 %len, 1
|
||
|
|
br i1 %cmp2, label %for.body.preheader, label %for.end
|
||
|
|
|
||
|
|
for.body.preheader: ; preds = %entry
|
||
|
|
br label %for.body
|
||
|
|
|
||
|
|
for.body: ; preds = %for.body, %for.body.preheader
|
||
|
|
%p.addr.05 = phi i16* [ %incdec.ptr, %for.body ], [ %p, %for.body.preheader ]
|
||
|
|
%len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %for.body.preheader ]
|
||
|
|
%res.03 = phi i32 [ %add, %for.body ], [ 0, %for.body.preheader ]
|
||
|
|
%incdec.ptr = getelementptr inbounds i16, i16* %p.addr.05, i32 1
|
||
|
|
%0 = load i16, i16* %p.addr.05, align 2
|
||
|
|
%conv = zext i16 %0 to i32
|
||
|
|
%add = add i32 %conv, %res.03
|
||
|
|
%sub = add nsw i32 %len.addr.04, -2
|
||
|
|
%cmp = icmp sgt i32 %sub, 1
|
||
|
|
br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge
|
||
|
|
|
||
|
|
for.cond.for.end_crit_edge: ; preds = %for.body
|
||
|
|
%extract.t = trunc i32 %add to i16
|
||
|
|
br label %for.end
|
||
|
|
|
||
|
|
for.end: ; preds = %for.cond.for.end_crit_edge, %entry
|
||
|
|
%res.0.lcssa.off0 = phi i16 [ %extract.t, %for.cond.for.end_crit_edge ], [ 0, %entry ]
|
||
|
|
ret i16 %res.0.lcssa.off0
|
||
|
|
}
|
||
|
|
|