196328 2019-03-27 16:53:07 -0700 B3ReduceStrength should mask large constants used in a shift 2019-03-28 12:46:40 -0700 1 1 1 Unclassified WebKit JavaScriptCore WebKit Nightly Build Unspecified Unspecified NEW P2 Trivial --- 196361 1 rmorisset rmorisset ews-watchlist keith_miller mark.lam msaboff saam oldest_to_newest 1521919 0 rmorisset 2019-03-27 16:53:07 -0700 The semantics of all shifts in B3 include a mask with either 31 or 63. So if we do a shift by a constant greater than that, we should do the mask directly on the constant. This would provide some useful canonicalization, reduce the need to materialize large constants, and could outright delete the shift if after the mask the constant is 0. 1521923 1 366129 rmorisset 2019-03-27 16:58:36 -0700 Created attachment 366129 Patch 366129 2019-03-27 16:58:36 -0700 2019-03-27 16:58:36 -0700 Patch patch196328 text/plain 2378 rmorisset ZGlmZiAtLWdpdCBhL1NvdXJjZS9KYXZhU2NyaXB0Q29yZS9DaGFuZ2VMb2cgYi9Tb3VyY2UvSmF2 YVNjcmlwdENvcmUvQ2hhbmdlTG9nCmluZGV4IDU4MGQyMzhmZjVlLi40MGI5YzI0MjRiMCAxMDA2 NDQKLS0tIGEvU291cmNlL0phdmFTY3JpcHRDb3JlL0NoYW5nZUxvZworKysgYi9Tb3VyY2UvSmF2 YVNjcmlwdENvcmUvQ2hhbmdlTG9nCkBAIC0xLDMgKzEsMTQgQEAKKzIwMTktMDMtMjcgIFJvYmlu IE1vcmlzc2V0ICA8cm1vcmlzc2V0QGFwcGxlLmNvbT4KKworICAgICAgICBCM1JlZHVjZVN0cmVu Z3RoIHNob3VsZCBtYXNrIGxhcmdlIGNvbnN0YW50cyB1c2VkIGluIGEgc2hpZnQKKyAgICAgICAg aHR0cHM6Ly9idWdzLndlYmtpdC5vcmcvc2hvd19idWcuY2dpP2lkPTE5NjMyOAorCisgICAgICAg IFJldmlld2VkIGJ5IE5PQk9EWSAoT09QUyEpLgorCisgICAgICAgIE5vIG5ldyB0ZXN0cyBhZGRl ZCwgYXMgdGhlcmUgYXJlIGFscmVhZHkgYSBidW5jaCBvZiByZWxldmFudCB0ZXN0cyBpbiB0ZXN0 YjMuCisgICAgICAgIEUuZy4gdGVzdFNobEFyZ0ltbSwgdGVzdFNobFNTaHJBcmdJbW0sIHRlc3RT aGxBcmdJbW0zMiwgdGVzdFNobFpTaHJBcmdJbW0zMiwgZXRjLi4KKyAgICAgICAgKiBiMy9CM1Jl ZHVjZVN0cmVuZ3RoLmNwcDoKKwogMjAxOS0wMy0yNSAgR3l1eW91bmcgS2ltICA8Z3l1eW91bmcu a2ltQHdlYmtpdC5vcmc+CiAKICAgICAgICAgUmVtb3ZlIE5hdmlnYXRvckNvbnRlbnRVdGlscyBp biBXZWJDb3JlL01vZHVsZXMKZGlmZiAtLWdpdCBhL1NvdXJjZS9KYXZhU2NyaXB0Q29yZS9iMy9C M1JlZHVjZVN0cmVuZ3RoLmNwcCBiL1NvdXJjZS9KYXZhU2NyaXB0Q29yZS9iMy9CM1JlZHVjZVN0 cmVuZ3RoLmNwcAppbmRleCAwZGIzZWFkODA0OC4uZDE2NTQ5MjM1MDcgMTAwNjQ0Ci0tLSBhL1Nv dXJjZS9KYXZhU2NyaXB0Q29yZS9iMy9CM1JlZHVjZVN0cmVuZ3RoLmNwcAorKysgYi9Tb3VyY2Uv SmF2YVNjcmlwdENvcmUvYjMvQjNSZWR1Y2VTdHJlbmd0aC5jcHAKQEAgLTI0NzYsMTcgKzI0NzYs MjQgQEAgcHJpdmF0ZToKIAogICAgIHZvaWQgaGFuZGxlU2hpZnRBbW91bnQoKQogICAgIHsKLSAg ICAgICAgLy8gU2hpZnQgYW55dGhpbmcgYnkgemVybyBpcyBpZGVudGl0eS4KLSAgICAgICAgaWYg KG1fdmFsdWUtPmNoaWxkKDEpLT5pc0ludDMyKDApKSB7Ci0gICAgICAgICAgICByZXBsYWNlV2l0 aElkZW50aXR5KG1fdmFsdWUtPmNoaWxkKDApKTsKLSAgICAgICAgICAgIHJldHVybjsKKyAgICAg ICAgaW50MzJfdCBtYXNrID0gc2l6ZW9mVHlwZShtX3ZhbHVlLT50eXBlKCkpICogOCAtIDE7Cisg ICAgICAgIGlmIChtX3ZhbHVlLT5jaGlsZCgxKS0+aGFzSW50MzIoKSkgeworICAgICAgICAgICAg Ly8gV2UgbWFzayBhbnkgc2hpZnQgdGhhdCB3b3VsZCBvdmVyZmxvdworICAgICAgICAgICAgaWYg KG1fdmFsdWUtPmNoaWxkKDEpLT5hc0ludDMyKCkgPiBtYXNrKSB7CisgICAgICAgICAgICAgICAg VmFsdWUqIG5ld0NvbnN0YW50ID0gbV9pbnNlcnRpb25TZXQuaW5zZXJ0PENvbnN0MzJWYWx1ZT4o bV9pbmRleCwgbV92YWx1ZS0+Y2hpbGQoMSktPm9yaWdpbigpLCBtX3ZhbHVlLT5jaGlsZCgxKS0+ YXNJbnQzMigpICYgbWFzayk7CisgICAgICAgICAgICAgICAgbV92YWx1ZS0+Y2hpbGQoMSkgPSBu ZXdDb25zdGFudDsKKyAgICAgICAgICAgIH0KKyAgICAgICAgICAgIC8vIFNoaWZ0IGFueXRoaW5n IGJ5IHplcm8gaXMgaWRlbnRpdHkuCisgICAgICAgICAgICBpZiAobV92YWx1ZS0+Y2hpbGQoMSkt PmlzSW50MzIoMCkpIHsKKyAgICAgICAgICAgICAgICByZXBsYWNlV2l0aElkZW50aXR5KG1fdmFs dWUtPmNoaWxkKDApKTsKKyAgICAgICAgICAgICAgICByZXR1cm47CisgICAgICAgICAgICB9CiAg ICAgICAgIH0KIAogICAgICAgICAvLyBUaGUgc2hpZnQgYWxyZWFkeSBtYXNrcyBpdHMgc2hpZnQg YW1vdW50LiBJZiB0aGUgc2hpZnQgYW1vdW50IGlzIGJlaW5nIG1hc2tlZCBieSBhCiAgICAgICAg IC8vIHJlZHVuZGFudCBhbW91bnQsIHRoZW4gcmVtb3ZlIHRoZSBtYXNrLiBGb3IgZXhhbXBsZSwK ICAgICAgICAgLy8gVHVybiB0aGlzOiBTaGwoQHgsIEJpdEFuZChAeSwgNjMpKQogICAgICAgICAv LyBJbnRvIHRoaXM6IFNobChAeCwgQHkpCi0gICAgICAgIHVuc2lnbmVkIG1hc2sgPSBzaXplb2ZU eXBlKG1fdmFsdWUtPnR5cGUoKSkgKiA4IC0gMTsKICAgICAgICAgaWYgKG1fdmFsdWUtPmNoaWxk KDEpLT5vcGNvZGUoKSA9PSBCaXRBbmQKICAgICAgICAgICAgICYmIG1fdmFsdWUtPmNoaWxkKDEp LT5jaGlsZCgxKS0+aGFzSW50MzIoKQogICAgICAgICAgICAgJiYgKG1fdmFsdWUtPmNoaWxkKDEp LT5jaGlsZCgxKS0+YXNJbnQzMigpICYgbWFzaykgPT0gbWFzaykgewo=