| Issue |
149347
|
| Summary |
[LoopVectorize] Miscompilation at -Os
|
| Labels |
miscompilation,
generated by fuzzer,
vectorization
|
| Assignees |
|
| Reporter |
dtcxzyw
|
Reproducer: https://alive2.llvm.org/ce/z/gVth4Q
```
; bin/opt -passes=loop-vectorize test.ll -S
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@g_126 = global i32 0
define i1 @src() {
entry:
br label %for.cond232.preheader.i.i.i.i
for.cond232.preheader.i.i.i.i: ; preds = %safe_mod_func_uint32_t_u_u.exit.i.i.i.i, %entry
%storemerge552.i.i.i.i = phi i16 [ 0, %entry ], [ %add302.i.i.i.i, %safe_mod_func_uint32_t_u_u.exit.i.i.i.i ]
br i1 true, label %safe_mod_func_uint32_t_u_u.exit.i.i.i.i, label %cond.false.i518.i.i.i.i
cond.false.i518.i.i.i.i: ; preds = %for.cond232.preheader.i.i.i.i
br label %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
safe_mod_func_uint32_t_u_u.exit.i.i.i.i: ; preds = %cond.false.i518.i.i.i.i, %for.cond232.preheader.i.i.i.i
%cond.i519.i.i.i.i = phi i32 [ 0, %cond.false.i518.i.i.i.i ], [ 1, %for.cond232.preheader.i.i.i.i ]
store i32 %cond.i519.i.i.i.i, ptr @g_126, align 4
%add302.i.i.i.i = add i16 %storemerge552.i.i.i.i, 1
%exitcond559.not.i.i.i.i = icmp eq i16 %add302.i.i.i.i, 3
br i1 %exitcond559.not.i.i.i.i, label %for.inc309.i.i.i.i, label %for.cond232.preheader.i.i.i.i
for.inc309.i.i.i.i: ; preds = %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
%0 = load i32, ptr @g_126, align 4
%tobool205.not.i.i.i.i = icmp eq i32 %0, 0
ret i1 %tobool205.not.i.i.i.i
}
```
Output:
```
define i1 @src() {
entry:
br i1 false, label %scalar.ph, label %vector.ph
vector.ph: ; preds = %entry
br label %vector.body
vector.body: ; preds = %vector.ph
store i32 0, ptr @g_126, align 4
br label %middle.block
middle.block: ; preds = %vector.body
br label %for.inc309.i.i.i.i
scalar.ph: ; preds = %entry
%bc.resume.val = phi i16 [ 0, %entry ]
br label %for.cond232.preheader.i.i.i.i
for.cond232.preheader.i.i.i.i: ; preds = %scalar.ph, %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
%storemerge552.i.i.i.i = phi i16 [ %bc.resume.val, %scalar.ph ], [ %add302.i.i.i.i, %safe_mod_func_uint32_t_u_u.exit.i.i.i.i ]
br i1 true, label %safe_mod_func_uint32_t_u_u.exit.i.i.i.i, label %cond.false.i518.i.i.i.i
cond.false.i518.i.i.i.i: ; preds = %for.cond232.preheader.i.i.i.i
br label %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
safe_mod_func_uint32_t_u_u.exit.i.i.i.i: ; preds = %cond.false.i518.i.i.i.i, %for.cond232.preheader.i.i.i.i
%cond.i519.i.i.i.i = phi i32 [ 0, %cond.false.i518.i.i.i.i ], [ 1, %for.cond232.preheader.i.i.i.i ]
store i32 %cond.i519.i.i.i.i, ptr @g_126, align 4
%add302.i.i.i.i = add i16 %storemerge552.i.i.i.i, 1
%exitcond559.not.i.i.i.i = icmp eq i16 %add302.i.i.i.i, 3
br i1 %exitcond559.not.i.i.i.i, label %for.inc309.i.i.i.i, label %for.cond232.preheader.i.i.i.i, !llvm.loop !0
for.inc309.i.i.i.i: ; preds = %middle.block, %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
%0 = load i32, ptr @g_126, align 4
%tobool205.not.i.i.i.i = icmp eq i32 %0, 0
ret i1 %tobool205.not.i.i.i.i
}
!0 = distinct !{!0, !1, !2}
!1 = !{!"llvm.loop.unroll.runtime.disable"}
!2 = !{!"llvm.loop.isvectorized", i32 1}
```
```
Transformation doesn't verify!
ERROR: Value mismatch
Example:
Source:
>> Jump to %for.cond232.preheader.i.i.i.i
i16 %storemerge552.i.i.i.i = #x0000 (0)
>> Jump to %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
i32 %cond.i519.i.i.i.i = #x00000001 (1)
i16 %add302.i.i.i.i = #x0001 (1)
i1 %exitcond559.not.i.i.i.i = #x0 (0)
>> Jump to %for.cond232.preheader.i.i.i.i#2
i16 %storemerge552.i.i.i.i#2 = #x0001 (1)
>> Jump to %safe_mod_func_uint32_t_u_u.exit.i.i.i.i#2
i32 %cond.i519.i.i.i.i#2 = #x00000001 (1)
i16 %add302.i.i.i.i#2 = #x0002 (2)
i1 %exitcond559.not.i.i.i.i#2 = #x0 (0)
>> Jump to %for.cond232.preheader.i.i.i.i#3
i16 %storemerge552.i.i.i.i#3 = #x0002 (2)
>> Jump to %safe_mod_func_uint32_t_u_u.exit.i.i.i.i#3
i32 %cond.i519.i.i.i.i#3 = #x00000001 (1)
i16 %add302.i.i.i.i#3 = #x0003 (3)
i1 %exitcond559.not.i.i.i.i#3 = #x1 (1)
>> Jump to %for.inc309.i.i.i.i
i32 %#0 = #x00000001 (1)
i1 %tobool205.not.i.i.i.i = #x0 (0)
SOURCE MEMORY STATE
===================
NON-LOCAL BLOCKS:
Block 0 > size: 4 align: 4 alloc type: 0 alive: true address: 4
Contents:
poison
Target:
>> Jump to %vector.ph
>> Jump to %vector.body
>> Jump to %middle.block
>> Jump to %for.inc309.i.i.i.i
i32 %#0 = #x00000000 (0)
i1 %tobool205.not.i.i.i.i = #x1 (1)
Source value: #x0 (0)
Target value: #x1 (1)
```
llvm version: 4bf82aebc0da985cf6b2e70812714875e8fa78fa
Log before LoopVectorize:
```
Entering function main
br label %for.cond232.preheader.i.i.i.i jump to %for.cond232.preheader.i.i.i.i
phi i16 %storemerge552.i.i.i.i -> i16 0
br i1 true, label %safe_mod_func_uint32_t_u_u.exit.i.i.i.i, label %cond.false.i518.i.i.i.i jump to %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
phi i32 %cond.i519.i.i.i.i -> i32 1
store i32 %cond.i519.i.i.i.i, ptr @g_126, align 4
%add302.i.i.i.i = add i16 %storemerge552.i.i.i.i, 1 -> i16 1
%exitcond559.not.i.i.i.i = icmp eq i16 %add302.i.i.i.i, 3 -> F
br i1 %exitcond559.not.i.i.i.i, label %for.inc309.i.i.i.i, label %for.cond232.preheader.i.i.i.i jump to %for.cond232.preheader.i.i.i.i
phi i16 %storemerge552.i.i.i.i -> i16 1
br i1 true, label %safe_mod_func_uint32_t_u_u.exit.i.i.i.i, label %cond.false.i518.i.i.i.i jump to %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
phi i32 %cond.i519.i.i.i.i -> i32 1
store i32 %cond.i519.i.i.i.i, ptr @g_126, align 4
%add302.i.i.i.i = add i16 %storemerge552.i.i.i.i, 1 -> i16 2
%exitcond559.not.i.i.i.i = icmp eq i16 %add302.i.i.i.i, 3 -> F
br i1 %exitcond559.not.i.i.i.i, label %for.inc309.i.i.i.i, label %for.cond232.preheader.i.i.i.i jump to %for.cond232.preheader.i.i.i.i
phi i16 %storemerge552.i.i.i.i -> i16 2
br i1 true, label %safe_mod_func_uint32_t_u_u.exit.i.i.i.i, label %cond.false.i518.i.i.i.i jump to %safe_mod_func_uint32_t_u_u.exit.i.i.i.i
phi i32 %cond.i519.i.i.i.i -> i32 1
store i32 %cond.i519.i.i.i.i, ptr @g_126, align 4
%add302.i.i.i.i = add i16 %storemerge552.i.i.i.i, 1 -> i16 3
%exitcond559.not.i.i.i.i = icmp eq i16 %add302.i.i.i.i, 3 -> T
br i1 %exitcond559.not.i.i.i.i, label %for.inc309.i.i.i.i, label %for.cond232.preheader.i.i.i.i jump to %for.inc309.i.i.i.i
%0 = load i32, ptr @g_126, align 4 -> i32 1
%tobool205.not.i.i.i.i = icmp eq i32 %0, 0 -> F
ret i1 %tobool205.not.i.i.i.i
Exiting function main
```
After LoopVectorize:
```
Entering function main
br i1 false, label %scalar.ph, label %vector.ph jump to %vector.ph
br label %vector.body jump to %vector.body
store i32 0, ptr @g_126, align 4
br label %middle.block jump to %middle.block
br label %for.inc309.i.i.i.i jump to %for.inc309.i.i.i.i
%0 = load i32, ptr @g_126, align 4 -> i32 0
%tobool205.not.i.i.i.i = icmp eq i32 %0, 0 -> T
ret i1 %tobool205.not.i.i.i.i
Exiting function main
```
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