Test source: git
Comments: LLVM PR57523
Source: <stdin>
-- 1. ModuleToFunctionPassAdaptor
-- 1. PassManager<Function> : Skipping NOP
-- 2. IRCEPass
----------------------------------------
define void @multiple_access_no_preloop(ptr %arr_a, ptr %a_len_ptr, ptr %arr_b, ptr %b_len_ptr, i32 %n) {
entry:
  %len.a = load i32, ptr %a_len_ptr, align 4
  %len.a_range = !range i32 %len.a, i32 0, i32 2147483647
  %len.b = load i32, ptr %b_len_ptr, align 4
  %len.b_range = !range i32 %len.b, i32 0, i32 2147483647
  %first.itr.check = icmp sgt i32 %n, 0
  br i1 %first.itr.check, label %loop, label %exit
loop:
  %idx = phi i32 [ 0, %entry ], [ %idx.next, %in.bounds.b ]
  %idx.next = add i32 %idx, 1
  %abc.a = icmp slt i32 %idx, %len.a_range
  br i1 %abc.a, label %in.bounds.a, label %out.of.bounds
in.bounds.a:
  %addr.a = gep ptr %arr_a, 4 x i32 %idx
  store i32 0, ptr %addr.a, align 4
  %abc.b = icmp slt i32 %idx, %len.b_range
  br i1 %abc.b, label %in.bounds.b, label %out.of.bounds
in.bounds.b:
  %addr.b = gep ptr %arr_b, 4 x i32 %idx
  store i32 4294967295, ptr %addr.b, align 4
  %next = icmp slt i32 %idx.next, %n
  br i1 %next, label %loop, label %exit
exit:
  ret void
out.of.bounds:
  ret void
}
Transformation seems to be correct! (syntactically equal)
-- 3. IRCEPass
----------------------------------------
define void @multiple_access_no_preloop(ptr %arr_a, ptr %a_len_ptr, ptr %arr_b, ptr %b_len_ptr, i32 %n) {
entry:
  %len.a = load i32, ptr %a_len_ptr, align 4
  %len.a_range = !range i32 %len.a, i32 0, i32 2147483647
  %len.b = load i32, ptr %b_len_ptr, align 4
  %len.b_range = !range i32 %len.b, i32 0, i32 2147483647
  %first.itr.check = icmp sgt i32 %n, 0
  br i1 %first.itr.check, label %loop, label %exit
loop:
  %idx = phi i32 [ 0, %entry ], [ %idx.next, %in.bounds.b ]
  %idx.next = add i32 %idx, 1
  %abc.a = icmp slt i32 %idx, %len.a_range
  br i1 %abc.a, label %in.bounds.a, label %out.of.bounds
in.bounds.a:
  %addr.a = gep ptr %arr_a, 4 x i32 %idx
  store i32 0, ptr %addr.a, align 4
  %abc.b = icmp slt i32 %idx, %len.b_range
  br i1 %abc.b, label %in.bounds.b, label %out.of.bounds
in.bounds.b:
  %addr.b = gep ptr %arr_b, 4 x i32 %idx
  store i32 4294967295, ptr %addr.b, align 4
  %next = icmp slt i32 %idx.next, %n
  br i1 %next, label %loop, label %exit
exit:
  ret void
out.of.bounds:
  ret void
}
=>
define void @multiple_access_no_preloop(ptr %arr_a, ptr %a_len_ptr, ptr %arr_b, ptr %b_len_ptr, i32 %n) {
entry:
  %len.a = load i32, ptr %a_len_ptr, align 4
  %len.a_range = !range i32 %len.a, i32 0, i32 2147483647
  %len.b = load i32, ptr %b_len_ptr, align 4
  %len.b_range = !range i32 %len.b, i32 0, i32 2147483647
  %first.itr.check = icmp sgt i32 %n, 0
  br i1 %first.itr.check, label %loop.preheader, label %exit
loop.preheader:
  %smin = smin i32 %len.b_range, %len.a_range
  %smin1 = smin i32 %smin, %n
  %exit.mainloop.at = smax i32 %smin1, 0
  %#0 = icmp slt i32 0, %exit.mainloop.at
  br i1 %#0, label %loop.preheader2, label %main.pseudo.exit
loop.preheader2:
  br label %loop
loop:
  %idx = phi i32 [ %idx.next, %in.bounds.b ], [ 0, %loop.preheader2 ]
  %idx.next = add nsw i32 %idx, 1
  br i1 1, label %in.bounds.a, label %out.of.bounds.loopexit3
in.bounds.a:
  %addr.a = gep ptr %arr_a, 4 x i32 %idx
  store i32 0, ptr %addr.a, align 4
  br i1 1, label %in.bounds.b, label %out.of.bounds.loopexit3
in.bounds.b:
  %addr.b = gep ptr %arr_b, 4 x i32 %idx
  store i32 4294967295, ptr %addr.b, align 4
  %#1 = icmp slt i32 %idx.next, %exit.mainloop.at
  br i1 %#1, label %loop, label %main.exit.selector
main.exit.selector:
  %idx.next.lcssa = phi i32 [ %idx.next, %in.bounds.b ]
  %#2 = icmp slt i32 %idx.next.lcssa, %n
  br i1 %#2, label %main.pseudo.exit, label %exit.loopexit
out.of.bounds.loopexit3:
  br label %out.of.bounds
main.pseudo.exit:
  %idx.copy = phi i32 [ 0, %loop.preheader ], [ %idx.next.lcssa, %main.exit.selector ]
  br label %postloop
postloop:
  br label %loop.postloop
loop.postloop:
  %idx.postloop = phi i32 [ %idx.next.postloop, %in.bounds.b.postloop ], [ %idx.copy, %postloop ]
  %idx.next.postloop = add i32 %idx.postloop, 1
  %abc.a.postloop = icmp slt i32 %idx.postloop, %len.a_range
  br i1 %abc.a.postloop, label %in.bounds.a.postloop, label %out.of.bounds.loopexit
in.bounds.a.postloop:
  %addr.a.postloop = gep ptr %arr_a, 4 x i32 %idx.postloop
  store i32 0, ptr %addr.a.postloop, align 4
  %abc.b.postloop = icmp slt i32 %idx.postloop, %len.b_range
  br i1 %abc.b.postloop, label %in.bounds.b.postloop, label %out.of.bounds.loopexit
in.bounds.b.postloop:
  %addr.b.postloop = gep ptr %arr_b, 4 x i32 %idx.postloop
  store i32 4294967295, ptr %addr.b.postloop, align 4
  %next.postloop = icmp slt i32 %idx.next.postloop, %n
  br i1 %next.postloop, label %loop.postloop, label %exit.loopexit.loopexit
exit.loopexit.loopexit:
  br label %exit.loopexit
exit.loopexit:
  br label %exit
exit:
  ret void
out.of.bounds.loopexit:
  br label %out.of.bounds
out.of.bounds:
  ret void
}
Transformation doesn't verify! (unsound)
ERROR: Source is more defined than target
Example:
ptr %arr_a = poison
ptr %a_len_ptr = pointer(non-local, block_id=1, offset=0) / Address=#x0000000004
ptr %arr_b = poison
ptr %b_len_ptr = pointer(non-local, block_id=4, offset=0) / Address=#x000000000c
i32 %n = #x00000002 (2)
Source:
i32 %len.a = #x00000000 (0)
i32 %len.a_range = #x00000000 (0)
i32 %len.b = poison
i32 %len.b_range = poison
i1 %first.itr.check = #x1 (1)
  >> Jump to %loop
i32 %idx = #x00000000 (0)
i32 %idx.next = #x00000001 (1)
i1 %abc.a = #x0 (0)
  >> Jump to %out.of.bounds
SOURCE MEMORY STATE
===================
NON-LOCAL BLOCKS:
Block 0 >	size: 0	align: 4	alloc type: 0	alive: false	address: 0
Block 1 >	size: 4	align: 1	alloc type: 0	alive: true	address: 4
Contents:
0: #x00000000
*: poison
Block 2 >	size: 1	align: 1	alloc type: 0	alive: true	address: 8
Contents:
0: poison
*: poison
Block 3 >	size: 3	align: 1	alloc type: 0	alive: true	address: 1
Block 4 >	size: 9	align: 1	alloc type: 0	alive: true	address: 12
Target:
i32 %len.a = #x00000000 (0)
i32 %len.a_range = #x00000000 (0)
i32 %len.b = poison
i32 %len.b_range = poison
i1 %first.itr.check = #x1 (1)
  >> Jump to %loop.preheader
i32 %smin = poison
i32 %smin1 = poison
i32 %exit.mainloop.at = poison
i1 %#0 = poison
UB triggered on br
Pass: IRCEPass
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' '-verify-loop-info' '-passes=irce' '-S' '-tv-smt-to=20000' '-tv-report-dir=/home/nlopes/alive2/build/logs' '-tv-smt-stats'
Wrote bitcode to: "/home/nlopes/alive2/build/logs/in_LIc1KNxO_3Rg7.bc"
------------------- SMT STATS -------------------
Num queries: 59
Num invalid: 0
Num skips:   0
Num trivial: 12 (16.9%)
Num timeout: 0 (0.0%)
Num errors:  0 (0.0%)
Num SAT:     42 (71.2%)
Num UNSAT:   17 (28.8%)
Alive2: Transform doesn't verify; aborting!
RUN: at line 2: /home/nlopes/alive2/build/opt-alive.sh -verify-loop-info -passes=irce -S < /bitbucket/nlopes/llvm/llvm/test/Transforms/IRCE/multiple-access-no-preloop.ll | /bitbucket/nlopes/llvm/build/bin/FileCheck /bitbucket/nlopes/llvm/llvm/test/Transforms/IRCE/multiple-access-no-preloop.ll + /home/nlopes/alive2/build/opt-alive.sh -verify-loop-info -passes=irce -S + /bitbucket/nlopes/llvm/build/bin/FileCheck /bitbucket/nlopes/llvm/llvm/test/Transforms/IRCE/multiple-access-no-preloop.ll FileCheck error: '<stdin>' is empty. FileCheck command line: /bitbucket/nlopes/llvm/build/bin/FileCheck /bitbucket/nlopes/llvm/llvm/test/Transforms/IRCE/multiple-access-no-preloop.ll