In certain cases it is possible that transient instructions such as
%reg = IMPLICIT_DEF as a single instruction in a basic block to reach
the MipsHazardSchedule pass. This patch teaches MipsHazardSchedule to
properly look through such cases.
Reviewers: vkalintiris, zoran.jovanovic
Differential Revision: https://reviews.llvm.org/D27209
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289529 91177308-0d34-0410-b5e6-96231b3b80d8
Rename AllVRegsAllocated to NoVRegs. This avoids the connotation of
running after register and simply describes that no vregs are used in
a machine function. With that we can simply compute the property and do
not need to dump/parse it in .mir files.
Differential Revision: http://reviews.llvm.org/D23850
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279698 91177308-0d34-0410-b5e6-96231b3b80d8
Avoid implicit conversions from MachineInstrBundleIterator to
MachineInstr* in the Mips backend, mainly by preferring MachineInstr&
over MachineInstr* when a pointer isn't nullable and using range-based
for loops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275141 91177308-0d34-0410-b5e6-96231b3b80d8
MipsHazardSchedule has to determine what the next physical machine instruction
is to decide whether to insert a nop. In case where a branch with a forbidden
slot appears at the end of a basic block, first *real* instruction of the next
physical basic block was determined using getFirstNonDebugInstr().
Unfortunately this only considers DBG_VALUEs and not other transient opcodes
such as EHLABEL. As EHLABEL passes the SafeInForbiddenSlot predicate and the
instruction after the EHLABEL can be a CTI, we observed test failures in the
LNT testsuite.
Reviewers: dsanders
Differential Review: http://reviews.llvm.org/D19051
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Summary:
This adds the same checks that were added in r264593 to all
target-specific passes that run after register allocation.
Reviewers: qcolombet
Subscribers: jyknight, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18525
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Summary:
MIPSR6 introduces a class of branches called compact branches. Unlike the
traditional MIPS branches which have a delay slot, compact branches do not
have a delay slot. The instruction following the compact branch is only
executed if the branch is not taken and must not be a branch.
It works by generating compact branches for MIPS32R6 when the delay slot
filler cannot fill a delay slot. Then, inspecting the generated code for
forbidden slot hazards (a compact branch with an adjacent branch or other
CTI) and inserting nops to clear this hazard.
Patch by Simon Dardis.
Reviewers: vkalintiris, dsanders
Subscribers: MatzeB, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D16353
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@263444 91177308-0d34-0410-b5e6-96231b3b80d8