constraints validation in reload pass

[Georg-Johann Lay]

srimeruva@cse.iitb.ac.in schrieb:
> can anyone explain where(the part of the code or function) constraints in
> machine descriptions are validated in reload pass of gcc.

Please do not start a new topic by answering to an other, already 
existing topic ("match_dup as internal operands" in this case).

This will mess up email relations and thus confuse threaded email programs.

Thanks.

Part of the constraint checking code is located in recog.c, for example 
constrain_operands.

Target specific constraint-checkiers are auto-generated from backend's 
constraints.md file. For that code, see insn-constraints.c and 
insn-preds.c in the build directory.

Reloading and register allocation itself is performed by reload*.c and 
ira*.c

Johann