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|
; RUN: opt -S -basicaa -licm < %s | FileCheck %s
; RUN: opt -aa-pipeline=basic-aa -passes='require<opt-remark-emit>,loop(licm)' -S %s | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
declare void @f() nounwind
; constant fold on first ieration
define i32 @test1(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test1(
entry:
; CHECK: %i1 = load i32, i32* %a, align 4
; CHECK-NEXT: br label %for.body
br label %for.body
for.body:
%iv = phi i32 [ 0, %entry ], [ %inc, %continue ]
%acc = phi i32 [ 0, %entry ], [ %add, %continue ]
%r.chk = icmp ult i32 %iv, 2000
br i1 %r.chk, label %continue, label %fail
continue:
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = add nuw nsw i32 %iv, 1
%exitcond = icmp eq i32 %inc, 1000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
; Same as test1, but with a floating point IR and fcmp
define i32 @test_fcmp(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test_fcmp(
entry:
; CHECK: %i1 = load i32, i32* %a, align 4
; CHECK-NEXT: br label %for.body
br label %for.body
for.body:
%iv = phi float [ 0.0, %entry ], [ %inc, %continue ]
%acc = phi i32 [ 0, %entry ], [ %add, %continue ]
%r.chk = fcmp olt float %iv, 2000.0
br i1 %r.chk, label %continue, label %fail
continue:
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = fadd float %iv, 1.0
%exitcond = fcmp ogt float %inc, 1000.0
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
; Count down from a.length w/entry guard
; TODO: currently unable to prove the following:
; ule i32 (add nsw i32 %len, -1), %len where len is [0, 512]
define i32 @test2(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test2(
entry:
%len = load i32, i32* %a, align 4, !range !{i32 0, i32 512}
%is.non.pos = icmp eq i32 %len, 0
br i1 %is.non.pos, label %fail, label %preheader
preheader:
%lenminusone = add nsw i32 %len, -1
br label %for.body
for.body:
%iv = phi i32 [ %lenminusone, %preheader ], [ %dec, %continue ]
%acc = phi i32 [ 0, %preheader ], [ %add, %continue ]
%r.chk = icmp ule i32 %iv, %len
br i1 %r.chk, label %continue, label %fail
continue:
; CHECK-LABEL: continue
; CHECK: %i1 = load i32, i32* %a, align 4
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%dec = add nsw i32 %iv, -1
%exitcond = icmp eq i32 %dec, 0
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
; trivially true for zero
define i32 @test3(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test3(
entry:
%len = load i32, i32* %a, align 4, !range !{i32 0, i32 512}
%is.zero = icmp eq i32 %len, 0
br i1 %is.zero, label %fail, label %preheader
preheader:
; CHECK: %i1 = load i32, i32* %a, align 4
; CHECK-NEXT: br label %for.body
br label %for.body
for.body:
%iv = phi i32 [ 0, %preheader ], [ %inc, %continue ]
%acc = phi i32 [ 0, %preheader ], [ %add, %continue ]
%r.chk = icmp ule i32 %iv, %len
br i1 %r.chk, label %continue, label %fail
continue:
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = add nuw nsw i32 %iv, 1
%exitcond = icmp eq i32 %inc, 1000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
; requires fact length is non-zero
; TODO: IsKnownNonNullFromDominatingConditions is currently only be done for
; pointers; should handle integers too
define i32 @test4(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test4(
entry:
%len = load i32, i32* %a, align 4, !range !{i32 0, i32 512}
%is.zero = icmp eq i32 %len, 0
br i1 %is.zero, label %fail, label %preheader
preheader:
br label %for.body
for.body:
%iv = phi i32 [ 0, %preheader ], [ %inc, %continue ]
%acc = phi i32 [ 0, %preheader ], [ %add, %continue ]
%r.chk = icmp ult i32 %iv, %len
br i1 %r.chk, label %continue, label %fail
continue:
; CHECK-LABEL: continue
; CHECK: %i1 = load i32, i32* %a, align 4
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = add nuw nsw i32 %iv, 1
%exitcond = icmp eq i32 %inc, 1000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
; variation on test1 with branch swapped
define i32 @test-brswap(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test-brswap(
entry:
; CHECK: %i1 = load i32, i32* %a, align 4
; CHECK-NEXT: br label %for.body
br label %for.body
for.body:
%iv = phi i32 [ 0, %entry ], [ %inc, %continue ]
%acc = phi i32 [ 0, %entry ], [ %add, %continue ]
%r.chk = icmp ugt i32 %iv, 2000
br i1 %r.chk, label %fail, label %continue
continue:
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = add nuw nsw i32 %iv, 1
%exitcond = icmp eq i32 %inc, 1000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
define i32 @test-nonphi(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test-nonphi(
entry:
br label %for.body
for.body:
; CHECK-LABEL: continue
; CHECK: %i1 = load i32, i32* %a, align 4
%iv = phi i32 [ 0, %entry ], [ %inc, %continue ]
%acc = phi i32 [ 0, %entry ], [ %add, %continue ]
%xor = xor i32 %iv, 72
%r.chk = icmp ugt i32 %xor, 2000
br i1 %r.chk, label %fail, label %continue
continue:
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = add nuw nsw i32 %iv, 1
%exitcond = icmp eq i32 %inc, 1000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
define i32 @test-wrongphi(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test-wrongphi(
entry:
br label %for.body
for.body:
%iv = phi i32 [ 0, %entry ], [ %inc, %continue ]
%acc = phi i32 [ 0, %entry ], [ %add, %continue ]
%cond = icmp ult i32 %iv, 500
br i1 %cond, label %dummy_block1, label %dummy_block2
dummy_block1:
br label %dummy_block2
dummy_block2:
%wrongphi = phi i32 [11, %for.body], [12, %dummy_block1]
%r.chk = icmp ugt i32 %wrongphi, 2000
br i1 %r.chk, label %fail, label %continue
continue:
; CHECK-LABEL: continue
; CHECK: %i1 = load i32, i32* %a, align 4
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = add nuw nsw i32 %iv, 1
%exitcond = icmp eq i32 %inc, 1000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
; This works because loop-simplify is run implicitly, but test for it anyways
define i32 @test-multiple-latch(i32* noalias nocapture readonly %a) nounwind uwtable {
; CHECK-LABEL: @test-multiple-latch(
entry:
; CHECK: %i1 = load i32, i32* %a, align 4
; CHECK-NEXT: br label %for.body
br label %for.body
for.body:
%iv = phi i32 [ 0, %entry ], [ %inc, %continue1 ], [ %inc, %continue2 ]
%acc = phi i32 [ 0, %entry ], [ %add, %continue1 ], [ %add, %continue2 ]
%r.chk = icmp ult i32 %iv, 2000
br i1 %r.chk, label %continue1, label %fail
continue1:
%i1 = load i32, i32* %a, align 4
%add = add nsw i32 %i1, %acc
%inc = add nuw nsw i32 %iv, 1
%cmp = icmp eq i32 %add, 0
br i1 %cmp, label %continue2, label %for.body
continue2:
%exitcond = icmp eq i32 %inc, 1000
br i1 %exitcond, label %for.cond.cleanup, label %for.body
for.cond.cleanup:
ret i32 %add
fail:
call void @f()
ret i32 -1
}
|
