Files
clang-p2996/llvm/test/Analysis/ScalarEvolution/trip-count-unknown-stride.ll
Arthur Eubanks 9adbb5cb3a [SCEV] Fix ScalarEvolution tests under NPM
Many tests use opt's -analyze feature, which does not translate well to
NPM and has better alternatives. The alternative here is to explicitly
add a pass that calls ScalarEvolution::print().

The legacy pass manager RUNs aren't changing, but they are now pinned to
the legacy pass manager.  For each legacy pass manager RUN, I added a
corresponding NPM RUN using the 'print<scalar-evolution>' pass. For
compatibility with update_analyze_test_checks.py and existing test
CHECKs, 'print<scalar-evolution>' now prints what -analyze prints per
function.

This was generated by the following Python script and failures were
manually fixed up:

import sys
for i in sys.argv:
    with open(i, 'r') as f:
        s = f.read()
    with open(i, 'w') as f:
        for l in s.splitlines():
            if "RUN:" in l and ' -analyze ' in l and '\\' not in l:
                f.write(l.replace(' -analyze ', ' -analyze -enable-new-pm=0 '))
                f.write('\n')
                f.write(l.replace(' -analyze ', ' -disable-output ').replace(' -scalar-evolution ', ' "-passes=print<scalar-evolution>" ').replace(" | ", " 2>&1 | "))
                f.write('\n')
            else:
                f.write(l)

There are a couple failures still in ScalarEvolution under NPM, but
those are due to other unrelated naming conflicts.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D83798
2020-07-16 11:24:07 -07:00

64 lines
2.2 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
; ScalarEvolution should be able to compute trip count of the loop by proving
; that this is not an infinite loop with side effects.
; CHECK: Determining loop execution counts for: @foo1
; CHECK: backedge-taken count is ((-1 + %n) /u %s)
; We should have a conservative estimate for the max backedge taken count for
; loops with unknown stride.
; CHECK: max backedge-taken count is -1
target datalayout = "e-m:e-p:32:32-f64:32:64-f80:32-n8:16:32-S128"
; Function Attrs: norecurse nounwind
define void @foo1(i32* nocapture %A, i32 %n, i32 %s) #0 {
entry:
%cmp4 = icmp sgt i32 %n, 0
br i1 %cmp4, label %for.body, label %for.end
for.body: ; preds = %entry, %for.body
%i.05 = phi i32 [ %add, %for.body ], [ 0, %entry ]
%arrayidx = getelementptr inbounds i32, i32* %A, i32 %i.05
%0 = load i32, i32* %arrayidx, align 4
%inc = add nsw i32 %0, 1
store i32 %inc, i32* %arrayidx, align 4
%add = add nsw i32 %i.05, %s
%cmp = icmp slt i32 %add, %n
br i1 %cmp, label %for.body, label %for.end
for.end: ; preds = %for.body, %entry
ret void
}
; Check that we are able to compute trip count of a loop without an entry guard.
; CHECK: Determining loop execution counts for: @foo2
; CHECK: backedge-taken count is ((-1 + (%n smax %s)) /u %s)
; We should have a conservative estimate for the max backedge taken count for
; loops with unknown stride.
; CHECK: max backedge-taken count is -1
; Function Attrs: norecurse nounwind
define void @foo2(i32* nocapture %A, i32 %n, i32 %s) #0 {
entry:
br label %for.body
for.body: ; preds = %entry, %for.body
%i.05 = phi i32 [ %add, %for.body ], [ 0, %entry ]
%arrayidx = getelementptr inbounds i32, i32* %A, i32 %i.05
%0 = load i32, i32* %arrayidx, align 4
%inc = add nsw i32 %0, 1
store i32 %inc, i32* %arrayidx, align 4
%add = add nsw i32 %i.05, %s
%cmp = icmp slt i32 %add, %n
br i1 %cmp, label %for.body, label %for.end
for.end: ; preds = %for.body, %entry
ret void
}