Instead of awkwardly encoding calling-convention information with ISD::CALL,
ISD::FORMAL_ARGUMENTS, ISD::RET, and ISD::ARG_FLAGS nodes, TargetLowering
provides three virtual functions for targets to override:
LowerFormalArguments, LowerCall, and LowerRet, which replace the custom
lowering done on the special nodes. They provide the same information, but
in a more immediately usable format.
This also reworks much of the target-independent tail call logic. The
decision of whether or not to perform a tail call is now cleanly split
between target-independent portions, and the target dependent portion
in IsEligibleForTailCallOptimization.
This also synchronizes all in-tree targets, to help enable future
refactoring and feature work.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78142 91177308-0d34-0410-b5e6-96231b3b80d8
calls were originally put in place because errs() at one time was
not unbuffered, and these print routines are commonly used with errs()
for debugging. However, errs() is now properly unbuffered, so the
flush calls are no longer needed. This significantly reduces the
number of write(2) calls for regular asm printing when there are many
small functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78137 91177308-0d34-0410-b5e6-96231b3b80d8
Get rid of yesterday's code to fix the register usage during isel.
Select the new DAG nodes to machine instructions. The new pre-alloc pass
to choose adjacent registers for these results is not done, so the
results of this will generally not assemble yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78136 91177308-0d34-0410-b5e6-96231b3b80d8
for ELF to work.
2) RIP addressing: Use SIB bytes for absolute relocations where RegBase=0,
IndexReg=0.
3) The JIT can get the real address of cstpools and jmptables during
code emission, fix that for object code emission
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78129 91177308-0d34-0410-b5e6-96231b3b80d8
For other VLDn and VSTn operations, we need to list the multiple registers
explicitly anyway, so there's no point in special-casing this one usage.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78109 91177308-0d34-0410-b5e6-96231b3b80d8
Imp-def is *not* allowed to redefine a live register.
Imp-use is *not* allowed to use a dead register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78106 91177308-0d34-0410-b5e6-96231b3b80d8
functions.
- Fix variant flattening when the variant embeds an operand reference.
- Ignore instructions which reference an operand multiple times (e.g., "xorb
$dst, $dst"), and operands which have extra flags (e.g., "$dst:subreg32").
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78099 91177308-0d34-0410-b5e6-96231b3b80d8
distinguish that the result is errno, so it can't use it to provide more
information about the error (it also exposes the numeric value of errno).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78098 91177308-0d34-0410-b5e6-96231b3b80d8
the masm backend. If anyone cares about masm in the future,
we'll have semantic sections it can hang off of.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78096 91177308-0d34-0410-b5e6-96231b3b80d8
For an undef operand, MO.getReg() is meaningless and we should not use it.
Undef operands should be skipped entirely.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78095 91177308-0d34-0410-b5e6-96231b3b80d8
When LowerExtract eliminates an EXTRACT_SUBREG with a kill flag, it moves the
kill flag to the place where the sub-register is killed. This can accidentally
overlap with the use of a sibling sub-register, and we have trouble.
In the test case we have this code:
Live Ins: %R0 %R1 %R2
%R2L<def> = EXTRACT_SUBREG %R2<kill>, 1
%R2H<def> = LOAD16fi <fi#-1>, 0, Mem:LD(2,4) [FixedStack-1 + 0]
%R1L<def> = EXTRACT_SUBREG %R1<kill>, 1
%R0L<def> = EXTRACT_SUBREG %R0<kill>, 1
%R0H<def> = ADD16 %R2H<kill>, %R2L<kill>, %AZ<imp-def>, %AN<imp-def>, %AC0<imp-def>, %V<imp-def>, %VS<imp-def>
subreg: CONVERTING: %R2L<def> = EXTRACT_SUBREG %R2<kill>, 1
subreg: eliminated!
subreg: killed here: %R0H<def> = ADD16 %R2H, %R2L, %R2<imp-use,kill>, %AZ<imp-def>, %AN<imp-def>, %AC0<imp-def>, %V<imp-def>, %VS<imp-def>
The kill flag on %R2 is moved to the last instruction, and the live range overlaps with the definition of %R2H:
*** Bad machine code: Redefining a live physical register ***
- function: f
- basic block: 0x18358c0 (#0)
- instruction: %R2H<def> = LOAD16fi <fi#-1>, 0, Mem:LD(2,4) [FixedStack-1 + 0]
Register R2H was defined but already live.
The fix is to replace EXTRACT_SUBREG with IMPLICIT_DEF instead of eliminating
it completely:
subreg: CONVERTING: %R2L<def> = EXTRACT_SUBREG %R2<kill>, 1
subreg: replace by: %R2L<def> = IMPLICIT_DEF %R2<kill>
Note that these IMPLICIT_DEF instructions survive to the asm output. It is
necessary to fix the stack-color-with-reg test case because of that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78093 91177308-0d34-0410-b5e6-96231b3b80d8
Implicit operands no longer get a free pass: Imp-use requires a live register
and imp-def requires a dead register.
There is also no special rule allowing redefinition of a sub-register when the
super-register is live. The super register must have imp-kill+imp-def operands
instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78090 91177308-0d34-0410-b5e6-96231b3b80d8
killed by another operand.
There is probably a better fix. Either 1) scavenger can look at other operands, or
2) livevariables can be smarter about kill markers. Patches welcome.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78072 91177308-0d34-0410-b5e6-96231b3b80d8
