nickdesaulniers added inline comments.
================ Comment at: llvm/lib/Target/AArch64/AArch64InstrInfo.cpp:1917 + .addDef(Reg) + .addImm(Options.StackProtectorGuardOffset >> 3); + else ---------------- dmgreen wrote: > nickdesaulniers wrote: > > dmgreen wrote: > > > What is StackProtectorGuardOffset, and could is be out of range for the > > > load? That is something that verify-machineinstrs won't currently check > > > for. > > It's passed from the front end; it's an offset added to the pointer load. > > The Linux kernel uses a value in 1100-1200 range. GCC will let you use > > whatever large value and keep appending adds for constants greater than > > 32200: https://godbolt.org/z/1xhbEPbKG, but YAGNI. > OK. It might be worth at least issuing a report_fatal_error if it is out of > the range of the instructions handled here. Otherwise the error might be > non-obvious, it just truncating the immediate during codegen. Indeed, in particular it looks like the range of LDR is 0-32760 which is sufficient for the kernel, but the range for LDUR is only -256-255, which is not. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D100919/new/ https://reviews.llvm.org/D100919 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
