Oliver Stannard 8dae8033b4 [AArch64] Improve v8.1-A code-gen for atomic load-subtract ...

Armv8.1-A added an atomic load-add instruction, but not a load-subtract
instruction. Our current code-generation for atomic load-subtract always
inserts a NEG instruction to negate it's argument, even if it could be
folded into a constant or another instruction.

This adds lowering early in selection DAG to convert a load-subtract
operation into a subtract and a load-add, allowing the normal DAG
optimisations to work on it.

I've left the old tablegen patterns in because they are still needed for
global isel.

Some of the tests in this patch are copied from D35375 by Chad Rosier (which
was abandoned).

Differential revision: https://reviews.llvm.org/D42477

llvm-svn: 324892

2018-02-12 14:22:03 +00:00

..

AArch64

[AArch64] Improve v8.1-A code-gen for atomic load-subtract

2018-02-12 14:22:03 +00:00

AMDGPU

Reapply "AMDGPU: Add 32-bit constant address space"

2018-02-09 16:57:57 +00:00

ARC

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ARM

[CodeGen] Add a -trap-unreachable option for debugging

2018-02-12 11:06:27 +00:00

AVR

[CodeGen] Unify the syntax of MBB successors in MIR and -debug output

2018-02-09 00:10:31 +00:00

BPF

bpf: Improve expanding logic in LowerSELECT_CC

2018-02-08 04:37:49 +00:00

Generic

[CodeGen] Unify the syntax of MBB successors in MIR and -debug output

2018-02-09 00:10:31 +00:00

Hexagon

[CodeGen] Add a -trap-unreachable option for debugging

2018-02-12 11:06:27 +00:00

Inputs

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Lanai

Followup on Proposal to move MIR physical register namespace to '$' sigil.

2018-01-31 22:04:26 +00:00

Mips

[mips] Fix 'l' constraint handling for types smaller than 32 bits

2018-02-12 12:21:55 +00:00

MIR

[GISel]: Verify COPIES involving generic registers.

2018-02-09 01:27:23 +00:00

MSP430

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Nios2

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NVPTX

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PowerPC

[MergeICmps] Re-commit rL324317 "Enable the MergeICmps Pass by default."

2018-02-07 09:58:55 +00:00

RISCV

[RISCV] Update two RISCV codegen tests after rL323991

2018-02-03 13:02:30 +00:00

SPARC

[MachineCopyPropagation] Extend pass to do COPY source forwarding

2018-02-01 18:54:01 +00:00

SystemZ

[SelectionDAG] Consider endianness in scalarizeVectorStore().

2018-02-02 08:48:02 +00:00

Thumb

[LivePhysRegs] Fix handling of return instructions.

2018-02-06 23:00:17 +00:00

Thumb2

Followup on Proposal to move MIR physical register namespace to '$' sigil.

2018-01-31 22:04:26 +00:00

WebAssembly

[WebAssembly] Add mechanisms for specifying an explicit import module name.

2018-02-09 23:13:22 +00:00

WinCFGuard

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WinEH

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X86

Revert r324835 "[X86] Reduce Store Forward Block issues in HW"

2018-02-12 12:43:39 +00:00

XCore

Emit smaller exception tables for non-SJLJ mode.

2018-02-09 17:13:37 +00:00