mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-01-19 20:34:38 +00:00
c5cbda12e9
// fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) ->
// (rotl x, y)
// fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) ->
// (rotr x, (sub 32, y))
Example: (x == 0xDEADBEEF and y == 4)
(x << 4) | (x >> 28)
=> 0xEADBEEF0 | 0x0000000D
=> 0xEADBEEFD
(rotl x, 4)
=> 0xEADBEEFD
(rotr x, 28)
=> 0xEADBEEFD
- Fix comment and code for second version. It wasn't using the rot* propertly.
// fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext r))) ->
// (rotr x, y)
// fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext r))) ->
// (rotl x, (sub 32, y))
(x << 28) | (x >> 4)
=> 0xD0000000 | 0x0DEADBEE
=> 0xDDEADBEE
(rotl x, 4)
=> 0xEADBEEFD
(rotr x, 28)
=> (0xEADBEEFD)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55575 91177308-0d34-0410-b5e6-96231b3b80d8
Low Level Virtual Machine (LLVM) ================================ This directory and its subdirectories contain source code for the Low Level Virtual Machine, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments. LLVM is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. Please see the HTML documentation provided in docs/index.html for further assistance with LLVM.