argument. The x86-64 ABI requires the incoming value of %rdi to
be copied to %rax on exit from a function that is returning a
large C struct.
Also, add a README-X86-64 entry detailing the missed optimization
opportunity and proposing an alternative approach.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50075 91177308-0d34-0410-b5e6-96231b3b80d8
Rename SDOperandImpl back to SDOperand.
Introduce the SDUse class that represents a use of the SDNode referred by
an SDOperand. Now it is more similar to Use/Value classes.
Patch is approved by Dan Gohman.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49795 91177308-0d34-0410-b5e6-96231b3b80d8
memcpy lowering code; this ensures that the size node has the desired
result type. This fixes a regression from r49572 with @llvm.memcpy.i64
on x86-32.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49761 91177308-0d34-0410-b5e6-96231b3b80d8
stack tracebacks on Darwin x86-64 won't work by default;
nevertheless, everybody but me thinks this is a good idea.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49663 91177308-0d34-0410-b5e6-96231b3b80d8
optimized x86-64 (and x86) calls so that they work (... at least for
my test cases).
Should fix the following problems:
Problem 1: When i introduced the optimized handling of arguments for
tail called functions (using a sequence of copyto/copyfrom virtual
registers instead of always lowering to top of the stack) i did not
handle byval arguments correctly e.g they did not work at all :).
Problem 2: On x86-64 after the arguments of the tail called function
are moved to their registers (which include ESI/RSI etc), tail call
optimization performs byval lowering which causes xSI,xDI, xCX
registers to be overwritten. This is handled in this patch by moving
the arguments to virtual registers first and after the byval lowering
the arguments are moved from those virtual registers back to
RSI/RDI/RCX.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49584 91177308-0d34-0410-b5e6-96231b3b80d8
on any current target and aren't optimized in DAGCombiner. Instead
of using intermediate nodes, expand the operations, choosing between
simple loads/stores, target-specific code, and library calls,
immediately.
Previously, the code to emit optimized code for these operations
was only used at initial SelectionDAG construction time; now it is
used at all times. This fixes some cases where rep;movs was being
used for small copies where simple loads/stores would be better.
This also cleans up code that checks for alignments less than 4;
let the targets make that decision instead of doing it in
target-independent code. This allows x86 to use rep;movs in
low-alignment cases.
Also, this fixes a bug that resulted in the use of rep;stos for
memsets of 0 with non-constant memory size when the alignment was
at least 4. It's better to use the library in this case, which
can be significantly faster when the size is large.
This also preserves more SourceValue information when memory
intrinsics are lowered into simple loads/stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49572 91177308-0d34-0410-b5e6-96231b3b80d8
MOVZQI2PQIrr. This would be better handled as a dag combine
(with the goal of eliminating the bitconvert) but I don't know
how to do that safely. Thoughts welcome.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49463 91177308-0d34-0410-b5e6-96231b3b80d8
is needed for the x86-64-ABI handling of structs that contain floating-point
members that are returned by value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49441 91177308-0d34-0410-b5e6-96231b3b80d8
Specifically, introduction of XXX::Create methods
for Users that have a potentially variable number of
Uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49277 91177308-0d34-0410-b5e6-96231b3b80d8
review feedback.
-enable-eh is still accepted but doesn't do anything.
EH intrinsics use Dwarf EH if the target supports that,
and are handled by LowerInvoke otherwise.
The separation of the EH table and frame move data is,
I think, logically figured out, but either one still
causes full EH info to be generated (not sure how to
split the metadata correctly).
MachineModuleInfo::needsFrameInfo is no longer used and
is removed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49064 91177308-0d34-0410-b5e6-96231b3b80d8
not marked nounwind, or for all functions when -enable-eh
is set, provided the target supports Dwarf EH.
llvm-gcc generates nounwind in the right places; other FEs
will need to do so also. Given such a FE, -enable-eh should
no longer be needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49006 91177308-0d34-0410-b5e6-96231b3b80d8
LLVM Value/Use does and MachineRegisterInfo/MachineOperand does.
This allows constant time for all uses list maintenance operations.
The idea was suggested by Chris. Reviewed by Evan and Dan.
Patch is tested and approved by Dan.
On normal use-cases compilation speed is not affected. On very big basic
blocks there are compilation speedups in the range of 15-20% or even better.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48822 91177308-0d34-0410-b5e6-96231b3b80d8
llvm's output .s files will go through gcc -std=c99
without triggering preprocesser errors. Approach
suggested by Daveed Vandevoorde.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48808 91177308-0d34-0410-b5e6-96231b3b80d8
other things, this allows the scheduler to unfold a load operand
in the 2008-01-08-SchedulerCrash.ll testcase, so it now successfully
clones the comparison to avoid a pushf+popf.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48777 91177308-0d34-0410-b5e6-96231b3b80d8
flags. This is needed by the new legalize types
infrastructure which wants to expand the 64 bit
constants previously used to hold the flags on
32 bit machines. There are two functional changes:
(1) in LowerArguments, if a parameter has the zext
attribute set then that is marked in the flags;
before it was being ignored; (2) PPC had some bogus
code for handling two word arguments when using the
ELF 32 ABI, which was hard to convert because of
the bogusness. As suggested by the original author
(Nicolas Geoffray), I've disabled it for the moment.
Tested with "make check" and the Ada ACATS testsuite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48640 91177308-0d34-0410-b5e6-96231b3b80d8
x86-64 return conventions correct, but was never enabled.
We can now do the "right thing" with multiple return values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48635 91177308-0d34-0410-b5e6-96231b3b80d8
This allows us to compile fp-stack-2results.ll into:
_test:
fldz
fld1
ret
which returns 1 in ST(0) and 0 in ST(1). This is needed for x86-64
_Complex long double.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48632 91177308-0d34-0410-b5e6-96231b3b80d8
