Differential Revision: https://reviews.llvm.org/D103161

This is a preparation to split the format header in smaller parts for the
upcoming patches.

Depends on D101723

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D102703

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D101723

Add translation to LLVM IR for the UpdateOp with host and device operands.
Translation is done with call using the runtime. This is done in a similar way as
D101504 and D102381.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D102382

The current full unroll cost model does a symbolic evaluation of the loop up to a fixed limit. That symbolic evaluation currently simplifies to constants, but we can generalize to arbitrary Values using the InstructionSimplify infrastructure at very low cost.

By itself, this enables some simplifications, but it's mainly useful when combined with the branch simplification over in D102928.

Differential Revision: https://reviews.llvm.org/D102934

Support virtual, physical and tied i128 register operands in inline assembly.

i128 is on SystemZ not really supported and is not a legal type and generally
such a value will be split into two i64 parts. There are however some
instructions that require a pair of two GPR64 registers contained in the GR128
bit reg class, which is untyped.

For inline assmebly operands, it proved to be very cumbersome to first follow
the general behavior of splitting an i128 operand into two parts and then
later rebuild the INLINEASM MI to have one GR128 register. Instead, some
minor common code changes were made to SelectionDAGBUilder to only create one
GR128 register part to begin with. In particular:

- getNumRegisters() now has an optional parameter "RegisterVT" which is
  passed by AddInlineAsmOperands() and GetRegistersForValue().

- The bitcasting in GetRegistersForValue is not performed if RegVT is
  Untyped.

- The RC for a tied use in AddInlineAsmOperands() is now computed either from
  the tied def (virtual register), or by getMinimalPhysRegClass() (physical
  register).

- InstrEmitter.cpp:EmitCopyFromReg() has been fixed so that the register
  class (DstRC) can also be computed for an illegal type.

In the SystemZ backend getNumRegisters(), splitValueIntoRegisterParts() and
joinRegisterPartsIntoValue() have been implemented to handle i128 operands.

Differential Revision: https://reviews.llvm.org/D100788

Review: Ulrich Weigand

Previously notification of the Server about semantic happened strictly
before notification of the AST thread.
Hence a racy Server could make a request (like semantic tokens) after
the notification, with the assumption that it'll be served fresh
content. But it wasn't true if AST thread wasn't notified about the
change yet.

This change reverses the order of those notifications to prevent racy
interactions.

Differential Revision: https://reviews.llvm.org/D102761

- Currently, LLVM supports symbols of the name "token1@token2".
- "token2" is used to identify whether an appropriate symbol reference can be used for the symbol.
- Now, if the symbol reference couldn't be found, the AsmParser usually emits an error, unless the backend is configured to accept the "@" in a symbol name
- Thus, this patch aims to do that. It sets the `AllowAtInName` attribute in the SystemZ backend for the HLASM dialect.
- Setting this attribute ensures that, if a particular symbol reference is found, it uses that. If it doesn't, and there exists an "@" in the symbol name, it will use that instead of explicitly erroring out.

Reviewed By: uweigand

Differential Revision: https://reviews.llvm.org/D103111

This patch fixes a bug in the AMDGPU Propagate Attributes pass where a call
instruction with a function pointer argument is identified as a user of the
passed function, and illegally replaces the called function of the
instruction with the function argument.

For example, given functions f and g with appropriate types, the following
illegal transformation could occur without this fix:
call void @f(void ()* @g)
-->
call void @g(void ()* @g.1)

The solution introduced in this patch is to prevent the cloning and
substitution if the instruction's called function and the function which
might be cloned do not match.

Reviewed By: arsenm, madhur13490

Differential Revision: https://reviews.llvm.org/D101847

- Currently, before printing a label in MCSymbol.cpp (MCSymbol::print), the current code "validates" the label that is to be printed.
- If it fails the validation step, then it prints the label within double quotes.
- However, the validation is provided as a virtual function in MCAsmInfo.h (i.e. isAcceptableChar() function). So we can override this for the AD_HLASM dialect in SystemZMCAsmInfo.cpp.

Reviewed By: uweigand

Differential Revision: https://reviews.llvm.org/D103091

VS 2019 16.11 (just released in Preview) is adding support for the
/std:c++20 option and bumping /std:c++latest to "post-c++20". This
updates clang-cl to match.

Differential revision: https://reviews.llvm.org/D103155

The previous code detect if a MBB is bottom block to determine if it is
a backedge of a loop. We should check latch block instead of bottom
block and we should check the header and the bottom block are in the
same loop.

Differential Revision: https://reviews.llvm.org/D103145

Conservatively use the instruction latency to compute the last write-back cycle.
Before this patch, the last write cycle computation was incorrect for store
instructions that didn't declare any register writes.

NFC.

When loop hints are passed via metadata, the allowReordering function
in LoopVectorizationLegality will allow the order of floating point
operations to be changed:

  bool allowReordering() const {
    // When enabling loop hints are provided we allow the vectorizer to change
    // the order of operations that is given by the scalar loop. This is not
    // enabled by default because can be unsafe or inefficient.

The -enable-strict-reductions flag introduced in D98435 will currently only
vectorize reductions in-loop if hints are used, since canVectorizeFPMath()
will return false if reordering is not allowed.

This patch changes canVectorizeFPMath() to query whether it is safe to
vectorize the loop with ordered reductions if no hints are used. For
testing purposes, an additional flag (-hints-allow-reordering) has been
added to disable the reordering behaviour described above.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D101836

Return "[LoopDeletion] Break backedge if we can prove that the loop is exited on 1st iteration" (try 2)

The patch was reverted due to compile time impact of contextual SCEV
queries. It also appeared that it introduced a miscompile on irreducible CFG.

Changes made:
1. isKnownPredicateAt is replaced with more lightweight isKnownPredicate;
2. Irreducible CFG in live code is now detected and excluded from processing.

Differential Revision: https://reviews.llvm.org/D102615

Baseline tests for:
D102698

The update script ( utils/update_test_checks.py ) warns against this.

The update script ( utils/update_test_checks.py ) warns against this.

Revert "Return "[LoopDeletion] Break backedge if we can prove that the loop is exited on 1st iteration""

This reverts commit 43d2e51c.

Commited wrong version.

The patch was reverted due to compile time impact of contextual SCEV
queries. It also appeared that it introduced a miscompile on irreducible CFG.

Changes made:
1. isKnownPredicateAt is replaced with more lightweight isKnownPredicate;
2. Irreducible CFG in live code is now detected and excluded from processing.

Differential Revision: https://reviews.llvm.org/D102615

Differential Revision: https://reviews.llvm.org/D103148

The existing LD1 patterns do not cover cases where result type does
not match the memory type. This happens when illegal vector types are
extended and scalarized, for example:

  load <2 x i16>* %v2i16

is lowered into:

  // first element
  (v4i32 (insert_subvector (v2i32 (scalar_to_vector (load anyext from i16)))))
  // other elements
  (v4i32 (insert_vector_elt (i32 (load anyext from i16)) idx))

Before this patch these patterns were compiled into LDR + INS.
Now they are compiled into LD1.

The problem was reported in
PR24820: LLVM Generates abysmal code in simple situation.

Differential Revision: https://reviews.llvm.org/D102938

Authored by Mikael Holmén. It demonstrated miscompile on irreducible
CFG with patch "[LoopDeletion] Break backedge if we can prove that the loop is exited on 1st iteration".
The patch is reverted. Checking in the test to make sure this bug
does not return.

Avoid duplicating the memory_order and memory_scope enum definitions.

Wrote about llvm/lib/MC subproject on https://llvm.org/docs/GettingStarted.html page.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D101047

Global values imply flags such as readable, writable, executable for the
sections that they will be placed in. Currently MC places all such
entries into the same section, using the first set of flags seen. This
can lead to situations in LTO where a writable global is placed in the
same named section as a readable global from another file, and the
section may not be marked writable.

D72194 ensures that mergeable globals with explicit sections are placed
in separate sections with compatible entry size, by emitting the
`unique` assembly syntax where appropriate. This change extends that
approach to include section flags, so that globals with different
section flags are emitted in separate unique sections.

Differential revision: https://reviews.llvm.org/D100944

Precursor to D100944. The logic for determining the unique ID had become
quite difficult to reason about, so I have factored this out into a
separate function.

Differential Revision: https://reviews.llvm.org/D102336

After D102847, these functions can be inlined.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D103075

This patch drops g_atmi_initialized and inlines the Initialize &
Finalize methods from Runtime class.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D102847

The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D103084

Match whats documented in the Intel AOM (+Agner) - PSHUFB xmm is really slow, and mmx/xmm vector shifts are half rate.

Noticed while working to get the cost tables to more closely match llvm-mca analysis, in this case for shifts and truncations.