mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-01-14 16:33:28 +00:00
00edf4c1d8
Previously it was only be able to detect problems if the pointer was a numerical value (eg inttoptr i32 1 to i32*), but not if it was an alloca or globa. The reason was the use of ComputeMaskedBits: imagine you have "alloca i8, align 2", and ask ComputeMaskedBits what it knows about the bits of the alloca pointer. It can tell you that the bottom bit is known zero (due to align 2) but it can't tell you that bit 1 is known one. That's because the address could be an even multiple of 2 rather than an odd multiple, eg it might be a multiple of 4. Thus trying to use KnownOne is ineffective in the case of an alloca as it will never have any bits set. Instead look explicitly for constant offsets from allocas and globals. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164595 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. If you're writing a package for LLVM, see docs/Packaging.html for our suggestions.