[AMDGPU] Lowering VGPR to SGPR copies to v_readfirstlane_b32 if profitable.

Since the divergence-driven instruction selection has been enabled for AMDGPU,
all the uniform instructions are expected

[AMDGPU] Lowering VGPR to SGPR copies to v_readfirstlane_b32 if profitable.

Since the divergence-driven instruction selection has been enabled for AMDGPU,
all the uniform instructions are expected to be selected to SALU form, except those not having one.
VGPR to SGPR copies appear in MIR to connect values producers and consumers. This change implements an algorithm
that evolves a reasonable tradeoff between the profit achieved from keeping the uniform instructions in SALU form
and overhead introduced by the data transfer between the VGPRs and SGPRs.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D128252

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[AMDGPU] Change use null for dead sdst to be gfx1030+

Pre gfx1030 null for sdst is different.
c97436f8b6e2 [AMDGPU] Use null for dead sdst operand - requires a change to make
it not apply to pre gfx

[AMDGPU] Change use null for dead sdst to be gfx1030+

Pre gfx1030 null for sdst is different.
c97436f8b6e2 [AMDGPU] Use null for dead sdst operand - requires a change to make
it not apply to pre gfx1030

Differential Revision: https://reviews.llvm.org/D127869

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[AMDGPU] Use null for dead sdst operand

Differential Revision: https://reviews.llvm.org/D127542

[AMDGPU] Move call clobbered return address registers s[30:31] to callee saved range

Currently the return address ABI registers s[30:31], which fall in the call
clobbered register range, are added a

[AMDGPU] Move call clobbered return address registers s[30:31] to callee saved range

Currently the return address ABI registers s[30:31], which fall in the call
clobbered register range, are added as a live-in on the function entry to
preserve its value when we have calls so that it gets saved and restored
around the calls.

But the DWARF unwind information (CFI) needs to track where the return address
resides in a frame and the above approach makes it difficult to track the
return address when the CFI information is emitted during the frame lowering,
due to the involvment of understanding the control flow.

This patch moves the return address ABI registers s[30:31] into callee saved
registers range and stops adding live-in for return address registers, so that
the CFI machinery will know where the return address resides when CSR
save/restore happen during the frame lowering.

And doing the above poses an issue that now the return instruction uses undefined
register `sgpr30_sgpr31`. This is resolved by hiding the return address register
use by the return instruction through the `SI_RETURN` pseudo instruction, which
doesn't take any input operands, until the `SI_RETURN` pseudo gets lowered to the
`S_SETPC_B64_return` during the `expandPostRAPseudo()`.

As an added benefit, this patch simplifies overall return instruction handling.

Note: The AMDGPU CFI changes are there only in the downstream code and another
version of this patch will be posted for review for the downstream code.

Reviewed By: arsenm, ronlieb

Differential Revision: https://reviews.llvm.org/D114652

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[AMDGPU] Extend pre-emit peephole to redundantly masked VCC

Extend pre-emit peephole for S_CBRANCH_VCC[N]Z to eliminate
redundant S_AND operations against EXEC for V_CMP results in VCC.
These occur

[AMDGPU] Extend pre-emit peephole to redundantly masked VCC

Extend pre-emit peephole for S_CBRANCH_VCC[N]Z to eliminate
redundant S_AND operations against EXEC for V_CMP results in VCC.
These occur after after register allocation when VCC has been
selected as the comparison destination.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D120202

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[CodeGen] Remove unneeded regex escaping in FileCheck patterns. NFC.

Take advantage of D117117 to simplify all {{\[}} to [ and {{\]}} to ].

Differential Revision: https://reviews.llvm.org/D117298

Revert "[Local] invertCondition: try modifying an existing ICmpInst"

This reverts commit a6b54ddaba2d5dc0f72dcc4591c92b9544eb0016.

Apparently it is not safe to modify the condition even if it passe

Revert "[Local] invertCondition: try modifying an existing ICmpInst"

This reverts commit a6b54ddaba2d5dc0f72dcc4591c92b9544eb0016.

Apparently it is not safe to modify the condition even if it passes the
hasOneUse test, because StructurizeCFG might have other references to
the condition that are not manifest in the IR use-def chains.

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[Local] invertCondition: try modifying an existing ICmpInst

This avoids various cases where StructurizeCFG would otherwise insert an
xor i1 instruction, and it since it generally runs late in the pi

[Local] invertCondition: try modifying an existing ICmpInst

This avoids various cases where StructurizeCFG would otherwise insert an
xor i1 instruction, and it since it generally runs late in the pipeline,
instcombine does not clean up the xor-of-cmp pattern.

Differential Revision: https://reviews.llvm.org/D118478

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[AMDGPU] Tweak some compares in wave32.ll test

This prevents the compares from being optimized away when D86578 lands,
which seems unintended.

Revert "[AMDGPU] Move call clobbered return address registers s[30:31] to callee saved range"

This reverts commit 9075009d1fd5f2bf9aa6c2f362d2993691a316b3.

Failed amdgpu runtime buildbot # 3514

[AMDGPU] Move call clobbered return address registers s[30:31] to callee saved range

Currently the return address ABI registers s[30:31], which fall in the call
clobbered register range, are added a

[AMDGPU] Move call clobbered return address registers s[30:31] to callee saved range

Currently the return address ABI registers s[30:31], which fall in the call
clobbered register range, are added as a live-in on the function entry to
preserve its value when we have calls so that it gets saved and restored
around the calls.

But the DWARF unwind information (CFI) needs to track where the return address
resides in a frame and the above approach makes it difficult to track the
return address when the CFI information is emitted during the frame lowering,
due to the involvment of understanding the control flow.

This patch moves the return address ABI registers s[30:31] into callee saved
registers range and stops adding live-in for return address registers, so that
the CFI machinery will know where the return address resides when CSR
save/restore happen during the frame lowering.

And doing the above poses an issue that now the return instruction uses undefined
register `sgpr30_sgpr31`. This is resolved by hiding the return address register
use by the return instruction through the `SI_RETURN` pseudo instruction, which
doesn't take any input operands, until the `SI_RETURN` pseudo gets lowered to the
`S_SETPC_B64_return` during the `expandPostRAPseudo()`.

As an added benefit, this patch simplifies overall return instruction handling.

Note: The AMDGPU CFI changes are there only in the downstream code and another
version of this patch will be posted for review for the downstream code.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D114652

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[AMDGPU] Do not generate ELF symbols for the local branch target labels

The compiler was generating symbols in the final code object for local
branch target labels. This bloats the code object, slow

[AMDGPU] Do not generate ELF symbols for the local branch target labels

The compiler was generating symbols in the final code object for local
branch target labels. This bloats the code object, slows down the loader,
and is only used to simplify disassembly.

Use '--symbolize-operands' with llvm-objdump to improve readability of the
branch target operands in disassembly.

Fixes: SWDEV-312223

Reviewed By: scott.linder

Differential Revision: https://reviews.llvm.org/D114273

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[AMDGPU] Simplify 64-bit division/remainder expansion

The old expansion open-coded a 64-bit addition in a strange way, by
adding the high parts *without* carry-in from the low part, and then
adding

[AMDGPU] Simplify 64-bit division/remainder expansion

The old expansion open-coded a 64-bit addition in a strange way, by
adding the high parts *without* carry-in from the low part, and then
adding the carry back in later on. Fixing this saves a couple of
instructions and makes the code much easier to understand.

Differential Revision: https://reviews.llvm.org/D113679

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[AMDGPU] MachineLICM cannot hoist VALU

MachineLoop::isLoopInvariant() returns false for all VALU
because of the exec use. Check TII::isIgnorableUse() to
allow hoisting.

That unfortunately results i

[AMDGPU] MachineLICM cannot hoist VALU

MachineLoop::isLoopInvariant() returns false for all VALU
because of the exec use. Check TII::isIgnorableUse() to
allow hoisting.

That unfortunately results in higher register consumption
since MachineLICM does not adequately estimate pressure.
Therefor I think it shall only be enabled after D107677 even
though it does not depend on it.

Differential Revision: https://reviews.llvm.org/D107859

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[AMDGPU] Fold immediates in the optimizeCompareInstr

Peephole works before the first SIFoldOperands so most of
the immediates are in registers.

Differential Revision: https://reviews.llvm.org/D1091

[AMDGPU] Fold immediates in the optimizeCompareInstr

Peephole works before the first SIFoldOperands so most of
the immediates are in registers.

Differential Revision: https://reviews.llvm.org/D109186

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[AMDGPU] Use S_BITCMP1_* to replace AND in optimizeCompareInstr

Differential Revision: https://reviews.llvm.org/D109082

[AMDGPU] Introduce optimizeCompareInstr

The following patterns are currently handled:

s_cmp_eq_u32 (s_and_b32 $src, 1), 1 => s_and_b32 $src, 1
s_cmp_eq_i32 (s_and_b32 $src, 1), 1 => s_and_b32 $src,

[AMDGPU] Introduce optimizeCompareInstr

The following patterns are currently handled:

s_cmp_eq_u32 (s_and_b32 $src, 1), 1 => s_and_b32 $src, 1
s_cmp_eq_i32 (s_and_b32 $src, 1), 1 => s_and_b32 $src, 1
s_cmp_eq_u64 (s_and_b64 $src, 1), 1 => s_and_b64 $src, 1
s_cmp_ge_u32 (s_and_b32 $src, 1), 1 => s_and_b32 $src, 1
s_cmp_ge_i32 (s_and_b32 $src, 1), 1 => s_and_b32 $src, 1
s_cmp_lg_u32 (s_and_b32 $src, 1), 0 => s_and_b32 $src, 1
s_cmp_lg_i32 (s_and_b32 $src, 1), 0 => s_and_b32 $src, 1
s_cmp_lg_u64 (s_and_b64 $src, 1), 0 => s_and_b64 $src, 1
s_cmp_gt_u32 (s_and_b32 $src, 1), 0 => s_and_b32 $src, 1
s_cmp_gt_i32 (s_and_b32 $src, 1), 0 => s_and_b32 $src, 1

Differential Revision: https://reviews.llvm.org/D109031

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[AMDGPU] enable scalar compare in truncate selection

Currently, the truncate selection dag node is expanded as a bitwise AND plus compare to 1. This change enables scalar comparison in the pattern

[AMDGPU] enable scalar compare in truncate selection

Currently, the truncate selection dag node is expanded as a bitwise AND plus compare to 1. This change enables scalar comparison in the pattern if the truncate node is uniform.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D108925

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[AMDGPU] Divergence-driven compare operations instruction selection

Description: This change enables the compare operations to be selected to SALU/VALU form
dependent of the SDNode dive

[AMDGPU] Divergence-driven compare operations instruction selection

Description: This change enables the compare operations to be selected to SALU/VALU form
dependent of the SDNode divergence flag.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D106079

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Revert rG939291041bb35b8088e3b61be2b8b3bc950f64a7 "[AMDGPU] Regenerate wave32.ll test checks"

This still breaks buildbots

[AMDGPU] Regenerate wave32.ll test checks

To simplify diff in future patch

[AMDGPU] Use s_add_i32 for address additions

This allows to convert the add instruction to s_addk_i32 and
v_add_nc_u32 instead of needing v_add_co_u32 when converting to a VALU
instruction.

Differe

[AMDGPU] Use s_add_i32 for address additions

This allows to convert the add instruction to s_addk_i32 and
v_add_nc_u32 instead of needing v_add_co_u32 when converting to a VALU
instruction.

Differential Revision: https://reviews.llvm.org/D103322

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Revert rGd70cbd1ce9b426f2c7e0e0f900769bbcbb300a95 "[AMDGPU] Regenerate wave32.ll tests"

This is failing on buildbots but not locally - not sure why

[AMDGPU] Regenerate wave32.ll tests

Keep the manual GFX10DEFWAVE checks for VGPRBlocks

[AMDGPU] Fix typo in regular expression checks. NFC.