-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 03/08/11 04:36, Georg-Johann Lay wrote:
> > IRA doues not take into account costs implied by generating new stack > slots and setting up frame pointer. AFAIK there is no hook to > influence that. How can a target describe costs generated by setting > up stack slots and accessing them? IRA isn't particularly good about accounting for prologue/epilogue costs, both the saves/restores and FP setup. Part of the problem is the cost is really amortized across potentially many allocnos which potentially use the callee-saved registers. Unfortunately, there's no way to know that apriori. It's an issue Vlad and I have discussed, but we haven't come to any kind of conclusions for how to better model the costs of the prologue/epilogue vs the savings of allocing more allocnos to callee-saved hard regs vs caller-saved hard regs or memory. jeff -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJNdlNBAAoJEBRtltQi2kC7ShUIAJV2DgMhDV+t4rltCnnK6mDS SKvAWBw9fYyenDmSHYyYR0ABZbltRe98Q2B1XsQw7Ah5e2zXD11Xmr5EzZ+W0+uE LPLWphMDSnaQpy20qwnDhlOpgH3hChZ/4KwhtL3HHgzTq6dFw+v8k2UI2CBaMe2N eTLy3YP4AbbYyvBPbwMUnyxurmbt4nz98lvCi6L+bqBV0iWMXTOY8hce3+aPj1ib 1a70eTEP8CD+PKCpq+xPkl3yVCcwKsOCyHhFxFHscBZGLtbOLhmBpdwED0eW0Jbe dUxIYJyxFAZp4djm6+RFosPDIVJe2fBt/jW/ZzhV3h1zlcMxZNt2qxWsQi+2Y7E= =Pjsd -----END PGP SIGNATURE-----
