In a naked function, the flag is never set and getPristineRegs() returns an
empty list. That means naked functions are able to clobber callee saved
registers, but that is the whole point of naked functions.
This fixes PR4716.
llvm-svn: 79096
In the included test case, a stack load was not included in DistanceMap. That
caused TransferDeadness to ignore the instruction, leading to a scavenger
assert.
llvm-svn: 79090
support for globals going into the appropriate sections with the flags.
This hopefully finishes unbreaking the previous behavior that I broke before.
llvm-svn: 79079
x86_64-apple-darwin10.
--- Reverse-merging r78895 into '.':
U test/CodeGen/PowerPC/2008-12-12-EH.ll
U lib/Target/DarwinTargetAsmInfo.cpp
--- Reverse-merging r78892 into '.':
U include/llvm/Target/DarwinTargetAsmInfo.h
U lib/Target/X86/X86TargetAsmInfo.cpp
U lib/Target/X86/X86TargetAsmInfo.h
U lib/Target/ARM/ARMTargetAsmInfo.h
U lib/Target/ARM/ARMTargetMachine.cpp
U lib/Target/ARM/ARMTargetAsmInfo.cpp
U lib/Target/PowerPC/PPCTargetAsmInfo.cpp
U lib/Target/PowerPC/PPCTargetAsmInfo.h
U lib/Target/PowerPC/PPCTargetMachine.cpp
G lib/Target/DarwinTargetAsmInfo.cpp
llvm-svn: 78919
The register scavenger maintains a DistanceMap that maps MI pointers to their
distance from the top of the current MBB. The DistanceMap is built
incrementally in forward() and in bulk in findFirstUse(). It is used by
scavengeRegister() to determine which candidate register has the longest
unused interval.
Unfortunately the DistanceMap contents can become outdated. The first time
scavengeRegister() is called, the DistanceMap is filled to cover the MBB. If
then instructions are inserted in the MBB (as they always are following
scavengeRegister()), the recorded distances are too short. This causes bad
behaviour in the included test case where a register use /after/ the current
position is ignored because findFirstUse() thinks is is /before/ the current
position. A "using an undefined register" assertion follows promptly.
The fix is to build a fresh DistanceMap at the top of scavengeRegister(), and
discard it after use. This means that DistanceMap is no longer needed as a
RegScavenger member variable, and forward() doesn't need to update it.
The fix then discloses issue number two in the same test case: The candidate
search in scavengeRegister() finds a CSR that has been saved in the prologue,
but is currently unused. It would be both inefficient and wrong to spill such
a register in the emergency spill slot. In the present case, the emergency
slot restore is placed immediately before the normal epilogue restore, leading
to a "Redefining a live register" assertion.
Fix number two: When scavengerRegister() stumbles upon an unused register that
is overwritten later in the MBB, return that register early. It is important
to verify that the register is defined later in the MBB, otherwise it might be
an unspilled CSR.
llvm-svn: 78650
the overloaded vector types allowed floating-point or integer vector elements.
Most of these operations actually depend on the element type, so bitcasting
was not an option.
If you include the vpadd intrinsics that I updated earlier, this gets rid
of 20 intrinsics.
llvm-svn: 78646
MERGE_VALUES nodes. Replacing the result values with the
operands in one MERGE_VALUES node may cause another
MERGE_VALUES node be CSE'd with the first one, and bring
its uses along, so that the first one isn't dead, as this
code expects. Fix this by iterating until the node is
really dead. This fixes PR4699.
llvm-svn: 78619
