Speculatively disable Dan's commits 143177 and 143179 to see if
authorDuncan Sands <baldrick@free.fr>
Fri, 28 Oct 2011 09:55:57 +0000 (09:55 +0000)
committerDuncan Sands <baldrick@free.fr>
Fri, 28 Oct 2011 09:55:57 +0000 (09:55 +0000)
commit62c1d00dfd38996f381edae55e1028b8e52a1107
treebbaae35320bfa8b4844c93b04d0fbdb86d98dc8f
parent6a7efcfc02ea5370fb0da66d750165a3ffe93ab7
Speculatively disable Dan's commits 143177 and 143179 to see if
it fixes the dragonegg self-host (it looks like gcc is miscompiled).
Original commit messages:
Eliminate LegalizeOps' LegalizedNodes map and have it just call RAUW
on every node as it legalizes them. This makes it easier to use
hasOneUse() heuristics, since unneeded nodes can be removed from the
DAG earlier.

Make LegalizeOps visit the DAG in an operands-last order. It previously
used operands-first, because LegalizeTypes has to go operands-first, and
LegalizeTypes used to be part of LegalizeOps, but they're now split.
The operands-last order is more natural for several legalization tasks.
For example, it allows lowering code for nodes with floating-point or
vector constants to see those constants directly instead of seeing the
lowered form (often constant-pool loads). This makes some things
somewhat more complicated today, though it ought to allow things to be
simpler in the future. It also fixes some bugs exposed by Legalizing
using RAUW aggressively.

Remove the part of LegalizeOps that attempted to patch up invalid chain
operands on libcalls generated by LegalizeTypes, since it doesn't work
with the new LegalizeOps traversal order. Instead, define what
LegalizeTypes is doing to be correct, and transfer the responsibility
of keeping calls from having overlapping calling sequences into the
scheduler.

Teach the scheduler to model callseq_begin/end pairs as having a
physical register definition/use to prevent calls from having
overlapping calling sequences. This is also somewhat complicated, though
there are ways it might be simplified in the future.

This addresses rdar://9816668, rdar://10043614, rdar://8434668, and others.
Please direct high-level questions about this patch to management.

Delete #if 0 code accidentally left in.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143188 91177308-0d34-0410-b5e6-96231b3b80d8
18 files changed:
lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
lib/CodeGen/SelectionDAG/SelectionDAG.cpp
lib/Target/ARM/ARMISelLowering.cpp
lib/Target/X86/X86ISelDAGToDAG.cpp
lib/Target/X86/X86ISelLowering.cpp
lib/Target/XCore/XCoreISelLowering.cpp
test/CodeGen/CellSPU/and_ops.ll
test/CodeGen/CellSPU/call_indirect.ll
test/CodeGen/CellSPU/nand.ll
test/CodeGen/CellSPU/or_ops.ll
test/CodeGen/CellSPU/select_bits.ll
test/CodeGen/CellSPU/struct_1.ll
test/CodeGen/Mips/cprestore.ll
test/CodeGen/Mips/largeimmprinting.ll
test/CodeGen/Thumb/2011-05-11-DAGLegalizer.ll
test/CodeGen/X86/sse3.ll