Consider this case:
vreg1 = A2_zxth vreg0 (1)
...
vreg2 = A2_zxth vreg1 (2)
Redundant instruction elimination could delete the instruction (1)
because the user (2) only cares about the low 16 bits. Then it could
delete (2) because the input is already zero-extended. The problem
is that the properties allowing each individual instruction to be
deleted depend on the existence of the other instruction, so either
one can be deleted, but not both.
The existing check for this situation in RIE was insufficient. The
fix is to update all dependent cells when an instruction is removed
(replaced via COPY) in RIE.
llvm-svn: 276792
Avoid implicit iterator conversions from MachineInstrBundleIterator to
MachineInstr* in the Hexagon backend, mostly by preferring MachineInstr&
over MachineInstr* and switching to range-based for loops.
There's a long tail of API cleanup here, but I'm planning to leave the
rest to the Hexagon maintainers. HexagonInstrInfo defines many of its
own predicates, and most of them still take MachineInstr*. Some of
those actually check for nullptr, so I didn't feel comfortable changing
them to MachineInstr& en masse.
llvm-svn: 275142
As suggested by clang-tidy's performance-unnecessary-copy-initialization.
This can easily hit lifetime issues, so I audited every change and ran the
tests under asan, which came back clean.
llvm-svn: 272126
Compiling Hexagon target with GCC 6 produces "error: should have been
declared inside" due to GCC PR c++/69657 which was merged.
Properly wrapping operator<<() definitions within the namespace llvm
fixes the issue.
Author: domagoj.stolfa
Differential Revision: http://reviews.llvm.org/D17281
llvm-svn: 261220
Some implicit ilist iterator conversions have crept back into Analysis,
Transforms, Hexagon, and llvm-stress. This removes them.
I'll commit a patch immediately after this to disallow them (in a
separate patch so that it's easy to revert if necessary).
llvm-svn: 252371
There are two things out of the ordinary in this commit. First, I made
a loop obviously "infinite" in HexagonInstrInfo.cpp. After checking if
an instruction was at the beginning of a basic block (in which case,
`break`), the loop decremented and checked the iterator for `nullptr` as
the loop condition. This has never been possible (the prev pointers are
always been circular, so even with the weird ilist/iplist
implementation, this isn't been possible), so I removed the condition.
Second, in HexagonAsmPrinter.cpp there was another case of comparing a
`MachineBasicBlock::instr_iterator` against `MachineBasicBlock::end()`
(which returns `MachineBasicBlock::iterator`). While not incorrect,
it's fragile. I switched this to `::instr_end()`.
All that said, no functionality change intended here.
llvm-svn: 250778
We can now run 32-bit programs with empty catch bodies. The next step
is to change PEI so that we get funclet prologues and epilogues.
llvm-svn: 246235
The standard containers are not designed to be inherited from, as
illustrated by the MSVC hacks for NodeOrdering. No functional change
intended.
llvm-svn: 242616
This includes code that is intended to be target-independent as well
as the Hexagon-specific details. This is just the framework without
any users.
llvm-svn: 241595
