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mchalupa / dg

[LLVM Static Slicer] Various program analyses, construction of dependence graphs and program slicing of LLVM bitcode.
MIT License
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pta-show tool not working due to llvm-pta-dump incorrect dot syntax output #455

Closed Toaster192 closed 3 months ago

Toaster192 commented 7 months ago

Either the llvm-pta-dump tool is being called with incorrect arguments in the pta-show script or there is an issue in llvm-pta-dump that leads to the output not being in the correct .dot syntax.

Examples:

$ cat _ps.dot | head 
main::  %1 = alloca i32, align 4
  -> main::  %1 = alloca i32, align 4
main::  %2 = alloca %struct.Node*, align 8
  -> main::  %2 = alloca %struct.Node*, align 8
main::  %3 = alloca %struct.Node*, align 8
  -> main::  %3 = alloca %struct.Node*, align 8
main::  %4 = alloca %struct.Node*, align 8
  -> main::  %4 = alloca %struct.Node*, align 8
main::  %5 = alloca %struct.Node*, align 8
  -> main::  %5 = alloca %struct.Node*, align 8

or

$ ./dgtool pta-show  hello.c 
INFO: Pointer analysis took 0 sec 2 ms
Error: _ps.dot: syntax error in line 1 near 'main'
[dgtool]: command return non-zero status
$ cat _ps.dot 
main::  %1 = alloca i32, align 4
  -> main::  %1 = alloca i32, align 4
mchalupa commented 7 months ago

Thanks for reporting it. This is indeed a bug. The behavior of llvm-pta-dump was changed when a generic API for pointer analyses was introduced. llvm-pta-dump now uses this API to show the points-to sets. Dumping to graphviz is a feature that dumps the internal representation of points-to analyses (the pointer graph) and therefore must be used together with -ir option.