| Issue |
158045
|
| Summary |
[InferAlignment] Miscompilation: unsafe raising load alignment for `inttoptr` constant causes UB
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
zitongzhoueric
|
To reproduce: https://alive2.llvm.org/ce/z/gLQst2
Not sure if this is a known issue.
```
----------------------------------------
define i8 @f() {
entry:
%p = inttoptr i64 40 to ptr
%v = load i8, ptr %p, align 1
ret i8 %v
}
=>
define i8 @f() {
entry:
%p = inttoptr i64 40 to ptr
%v = load i8, ptr %p, align 8
ret i8 %v
}
Transformation doesn't verify!
ERROR: Source is more defined than target
Example:
Source:
ptr %p = phy-ptr(addr=40) / Address=#x0000000000000028
i8 %v = poison
SOURCE MEMORY STATE
===================
NON-LOCAL BLOCKS:
Block 0 > size: 0 align: 1 alloc type: 0 alive: false address: #x0000000000000000
Block 1 > size: 12 align: 1 alloc type: 0 alive: true address: #x000000000000001d
Target:
ptr %p = phy-ptr(addr=40) / Address=#x0000000000000028
i8 %v = UB triggered!
TARGET MEMORY STATE
===================
NON-LOCAL BLOCKS:
Block 0 > size: 0 align: 1 alloc type: 0 alive: false address: #x0000000000000000
Block 1 > size: 12 align: 1 alloc type: 0 alive: true address: #x000000000000001d
Summary:
0 correct transformations
1 incorrect transformations
0 failed-to-prove transformations
0 Alive2 errors
```
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