kgraft-analysis-tool

kgraft-analysis-tool is a simple tool capable of showing IPA cloning decisions made by modified version of the GCC compiler: https://github.com/marxin/gcc/tree/dump-ipa-clones

Having a modifed function foo, the tool displays all functions that can be affected by a change applied to the function foo. The most common case is propagation via inlining, however there are another IPA passes (IPA split, IPA constant propagation, etc.) that can be eventually generate clones that are inlined to a function.

Usages

$ gcc /home/marxin/Programming/linux/aesni-intel_glue.i -O2 -fdump-ipa-clones -c
$ ./kgraft-ipa-analysis.py aesni-intel_glue.i.000i.ipa-clones

[..skipped..]
Function: fls64/63 (./arch/x86/include/asm/bitops.h:479:90)
  inlining to: __ilog2_u64/132 (include/linux/log2.h:40:5)
    inlining to: ablkcipher_request_alloc/1639 (include/linux/crypto.h:979:82)
      constprop: ablkcipher_request_alloc.constprop.8/3198 (include/linux/crypto.h:979:82)
    inlining to: helper_rfc4106_decrypt/3007 (arch/x86/crypto/aesni-intel_glue.c:1016:12)
    inlining to: helper_rfc4106_encrypt/3006 (arch/x86/crypto/aesni-intel_glue.c:939:12)

  Affected functions: 5
    __ilog2_u64/132 (include/linux/log2.h:40:5)
    ablkcipher_request_alloc/1639 (include/linux/crypto.h:979:82)
    ablkcipher_request_alloc.constprop.8/3198 (include/linux/crypto.h:979:82)
    helper_rfc4106_decrypt/3007 (arch/x86/crypto/aesni-intel_glue.c:1016:12)
    helper_rfc4106_encrypt/3006 (arch/x86/crypto/aesni-intel_glue.c:939:12)
[..skipped..]

The tool can be easily used to display just a single function:

$ ./kgraft-ipa-analysis.py --symbol=scatterwalk_unmap aesni-intel_glue.i.000i.ipa-clones
Function: scatterwalk_unmap/2930 (include/crypto/scatterwalk.h:81:60)
  isra: scatterwalk_unmap.isra.2/3142 (include/crypto/scatterwalk.h:81:60)
    inlining to: helper_rfc4106_decrypt/3007 (arch/x86/crypto/aesni-intel_glue.c:1016:12)
    inlining to: helper_rfc4106_decrypt/3007 (arch/x86/crypto/aesni-intel_glue.c:1016:12)
    inlining to: helper_rfc4106_encrypt/3006 (arch/x86/crypto/aesni-intel_glue.c:939:12)

  Affected functions: 3
    scatterwalk_unmap.isra.2/3142 (include/crypto/scatterwalk.h:81:60)
    helper_rfc4106_decrypt/3007 (arch/x86/crypto/aesni-intel_glue.c:1016:12)
    helper_rfc4106_encrypt/3006 (arch/x86/crypto/aesni-intel_glue.c:939:12)