Test source: git
Source: /bitbucket/nlopes/llvm/llvm/test/Transforms/LoopVectorize/single-early-exit-cond-poison.ll
-- 1. ModuleToFunctionPassAdaptor
-- 1. PassManager<Function> : Skipping NOP
-- 2. LoopVectorizePass
----------------------------------------
define i32 @f(i32 noundef %g) noundef {
entry:
br label %loop.header
loop.header:
%iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ]
%mul = shl nsw nuw i32 %iv, 3
%shr = ashr i32 noundef %g, %mul
%early.cond = icmp eq i32 %shr, 0
br i1 %early.cond, label %loop.latch, label %return
loop.latch:
%iv.next = add nsw nuw i32 %iv, 1
%ec = icmp eq i32 %iv.next, 8
br i1 %ec, label %return, label %loop.header
return:
%res = phi i32 [ %shr, %loop.latch ], [ %iv, %loop.header ]
ret i32 %res
}
Transformation seems to be correct! (syntactically equal)
-- 3. LoopVectorizePass
----------------------------------------
define i32 @f(i32 noundef %g) noundef {
entry:
br label %loop.header
loop.header:
%iv = phi i32 [ 0, %entry ], [ %iv.next, %loop.latch ]
%mul = shl nsw nuw i32 %iv, 3
%shr = ashr i32 noundef %g, %mul
%early.cond = icmp eq i32 %shr, 0
br i1 %early.cond, label %loop.latch, label %return
loop.latch:
%iv.next = add nsw nuw i32 %iv, 1
%ec = icmp eq i32 %iv.next, 8
br i1 %ec, label %return, label %loop.header
return:
%res = phi i32 [ %shr, %loop.latch ], [ %iv, %loop.header ]
ret i32 %res
}
=>
declare i64 @llvm.experimental.cttz.elts.i64.v4i1(<4 x i1>, i1) nofree willreturn memory(none)
define i32 @f(i32 noundef %g) noundef {
entry:
br i1 0, label %scalar.ph, label %vector.ph
vector.ph:
%broadcast.splatinsert = insertelement <4 x i32> poison, i32 noundef %g, i64 0
%broadcast.splat = shufflevector <4 x i32> %broadcast.splatinsert, <4 x i32> poison, 0, 0, 0, 0
br label %vector.body
vector.body:
%index = phi i32 [ 0, %vector.ph ], [ %index.next, %vector.body ]
%vec.ind = phi <4 x i32> [ { 0, 1, 2, 3 }, %vector.ph ], [ %vec.ind.next, %vector.body ]
%step.add = add <4 x i32> %vec.ind, { 4, 4, 4, 4 }
%#0 = shl nsw nuw <4 x i32> %vec.ind, { 3, 3, 3, 3 }
%#1 = shl nsw nuw <4 x i32> %step.add, { 3, 3, 3, 3 }
%#2 = ashr <4 x i32> %broadcast.splat, %#0
%#3 = ashr <4 x i32> %broadcast.splat, %#1
%#4 = icmp ne <4 x i32> %#2, { 0, 0, 0, 0 }
%#5 = icmp ne <4 x i32> %#3, { 0, 0, 0, 0 }
%index.next = add nuw i32 %index, 8
%#6 = or <4 x i1> %#4, %#5
%#7 = reduce_or <4 x i1> %#6
%vec.ind.next = add <4 x i32> %step.add, { 4, 4, 4, 4 }
br i1 1, label %middle.split, label %vector.body
middle.split:
%#8 = extractelement <4 x i32> %#3, i32 3
br i1 %#7, label %vector.early.exit, label %middle.block
vector.early.exit:
%#9 = call i64 @llvm.experimental.cttz.elts.i64.v4i1(<4 x i1> %#5, i1 1) nofree willreturn memory(none)
%#10 = add i64 4, %#9
%#11 = call i64 @llvm.experimental.cttz.elts.i64.v4i1(<4 x i1> %#4, i1 1) nofree willreturn memory(none)
%#12 = add i64 0, %#11
%#13 = icmp ne i64 %#11, 4
%#14 = select i1 %#13, i64 %#12, i64 %#10
%#15 = trunc i64 %#14 to i32
%#16 = add i32 %index, %#15
br label %return
middle.block:
br label %return
scalar.ph:
br label %loop.header
loop.header:
%iv = phi i32 [ 0, %scalar.ph ], [ %iv.next, %loop.latch ]
%mul = shl nsw nuw i32 %iv, 3
%shr = ashr i32 noundef %g, %mul
%early.cond = icmp eq i32 %shr, 0
br i1 %early.cond, label %loop.latch, label %return
loop.latch:
%iv.next = add nsw nuw i32 %iv, 1
%ec = icmp eq i32 %iv.next, 8
br i1 %ec, label %return, label %loop.header
return:
%res = phi i32 [ %shr, %loop.latch ], [ %iv, %loop.header ], [ %#8, %middle.block ], [ %#16, %vector.early.exit ]
ret i32 %res
}
Transformation doesn't verify! (unsound)
ERROR: Source is more defined than target
Example:
i32 noundef %g = #x00000001 (1)
Source:
>> Jump to %loop.header
i32 %iv = #x00000000 (0)
i32 %mul = #x00000000 (0)
i32 %shr = #x00000001 (1)
i1 %early.cond = #x0 (0)
>> Jump to %return
i32 %res = #x00000000 (0)
SOURCE MEMORY STATE
===================
NON-LOCAL BLOCKS:
Block 0 > size: 0 align: 1 alloc type: 0 alive: false address: 0
Target:
>> Jump to %vector.ph
<4 x i32> %broadcast.splatinsert = < #x00000001 (1), poison, poison, poison >
<4 x i32> %broadcast.splat = < #x00000001 (1), #x00000001 (1), #x00000001 (1), #x00000001 (1) >
>> Jump to %vector.body
i32 %index = #x00000000 (0)
<4 x i32> %vec.ind = < #x00000000 (0), #x00000001 (1), #x00000002 (2), #x00000003 (3) >
<4 x i32> %step.add = < #x00000004 (4), #x00000005 (5), #x00000006 (6), #x00000007 (7) >
<4 x i32> %#0 = < #x00000000 (0), #x00000008 (8), #x00000010 (16), #x00000018 (24) >
<4 x i32> %#1 = < #x00000020 (32), #x00000028 (40), #x00000030 (48), #x00000038 (56) >
<4 x i32> %#2 = < #x00000001 (1), #x00000000 (0), #x00000000 (0), #x00000000 (0) >
<4 x i32> %#3 = < poison, poison, poison, poison >
<4 x i1> %#4 = < #x1 (1), #x0 (0), #x0 (0), #x0 (0) >
<4 x i1> %#5 = < poison, poison, poison, poison >
i32 %index.next = #x00000008 (8)
<4 x i1> %#6 = < poison, poison, poison, poison >
i1 %#7 = poison
<4 x i32> %vec.ind.next = < #x00000008 (8), #x00000009 (9), #x0000000a (10), #x0000000b (11) >
>> Jump to %middle.split
i32 %#8 = poison
UB triggered on br
Pass: LoopVectorizePass
Command line: '/home/nlopes/llvm/build/bin/opt' '-load=/home/nlopes/alive2/build/tv/tv.so' '-load-pass-plugin=/home/nlopes/alive2/build/tv/tv.so' '-tv-exit-on-error' '-p' 'loop-vectorize' '-force-vector-width=4' '-force-vector-interleave=2' '-S' '/bitbucket/nlopes/llvm/llvm/test/Transforms/LoopVectorize/single-early-exit-cond-poison.ll' '-tv-smt-to=20000' '-tv-report-dir=/home/nlopes/alive2/build/logs' '-tv-smt-stats'
Wrote bitcode to: "/home/nlopes/alive2/build/logs/single-early-exit-cond-poison_zl33CwoV_ZY3D.bc"
------------------- SMT STATS -------------------
Num queries: 9
Num invalid: 0
Num skips: 0
Num trivial: 41 (82.0%)
Num timeout: 0 (0.0%)
Num errors: 0 (0.0%)
Num SAT: 8 (88.9%)
Num UNSAT: 1 (11.1%)
Alive2: Transform doesn't verify; aborting!
/home/nlopes/alive2/build/opt-alive.sh -p loop-vectorize -force-vector-width=4 -force-vector-interleave=2 -S /bitbucket/nlopes/llvm/llvm/test/Transforms/LoopVectorize/single-early-exit-cond-poison.ll | /bitbucket/nlopes/llvm/build/bin/FileCheck --check-prefix=VF4IC2 /bitbucket/nlopes/llvm/llvm/test/Transforms/LoopVectorize/single-early-exit-cond-poison.ll # RUN: at line 2 + /home/nlopes/alive2/build/opt-alive.sh -p loop-vectorize -force-vector-width=4 -force-vector-interleave=2 -S /bitbucket/nlopes/llvm/llvm/test/Transforms/LoopVectorize/single-early-exit-cond-poison.ll + /bitbucket/nlopes/llvm/build/bin/FileCheck --check-prefix=VF4IC2 /bitbucket/nlopes/llvm/llvm/test/Transforms/LoopVectorize/single-early-exit-cond-poison.ll FileCheck error: '<stdin>' is empty. FileCheck command line: /bitbucket/nlopes/llvm/build/bin/FileCheck --check-prefix=VF4IC2 /bitbucket/nlopes/llvm/llvm/test/Transforms/LoopVectorize/single-early-exit-cond-poison.ll