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Implement the WaveActiveBitOr HLSL Function #99167

@farzonl

Description

@farzonl
  • Implement WaveActiveBitOr clang builtin,
  • Link WaveActiveBitOr clang builtin with hlsl_intrinsics.h
  • Add sema checks for WaveActiveBitOr to CheckHLSLBuiltinFunctionCall in SemaChecking.cpp
  • Add codegen for WaveActiveBitOr to EmitHLSLBuiltinExpr in CGBuiltin.cpp
  • Add codegen tests to clang/test/CodeGenHLSL/builtins/WaveActiveBitOr.hlsl
  • Add sema tests to clang/test/SemaHLSL/BuiltIns/WaveActiveBitOr-errors.hlsl
  • Create the int_dx_WaveActiveBitOr intrinsic in IntrinsicsDirectX.td
  • Create the DXILOpMapping of int_dx_WaveActiveBitOr to 120 in DXIL.td
  • Create the WaveActiveBitOr.ll and WaveActiveBitOr_errors.ll tests in llvm/test/CodeGen/DirectX/
  • Create the int_spv_WaveActiveBitOr intrinsic in IntrinsicsSPIRV.td
  • In SPIRVInstructionSelector.cpp create the WaveActiveBitOr lowering and map it to int_spv_WaveActiveBitOr in SPIRVInstructionSelector::selectIntrinsic.
  • Create SPIR-V backend test case in llvm/test/CodeGen/SPIRV/hlsl-intrinsics/WaveActiveBitOr.ll

DirectX

DXIL Opcode DXIL OpName Shader Model Shader Stages
120 WaveActiveBit 6.0 ('library', 'compute', 'amplification', 'mesh', 'pixel', 'vertex', 'hull', 'domain', 'geometry', 'raygeneration', 'intersection', 'anyhit', 'closesthit', 'miss', 'callable', 'node')

SPIR-V

OpGroupNonUniformBitwiseOr:

Description:

A bitwise or group operation of all Value operands
contributed by active invocations in the
group.

Result Type must be a scalar or vector of integer
type
.

Execution is a Scope that identifies the group of
invocations affected by this command. It must be Subgroup.

The identity I for Operation is 0. If Operation is
ClusteredReduce, ClusterSize must be present.

The type of Value must be the same as Result Type.

ClusterSize is the size of cluster to use. ClusterSize must be a
scalar of integer type, whose Signedness operand is 0.
ClusterSize must come from a constant
instruction
. Behavior is undefined unless
ClusterSize is at least 1 and a power of 2. If ClusterSize is
greater than the size of the group, executing this instruction
results in undefined behavior.

Capability:
GroupNonUniformArithmetic, GroupNonUniformClustered,
GroupNonUniformPartitionedNV

Missing before version 1.3.

Word Count Opcode Results Operands

6 + variable

360

<id>
Result Type

Result <id>

Scope <id>
Execution

Group Operation
Operation

<id>
Value

Optional
<id>
ClusterSize

Test Case(s)

Example 1

//dxc WaveActiveBitOr_test.hlsl -T lib_6_8 -enable-16bit-types -O0

export uint4 fn(uint4 p1) {
    return WaveActiveBitOr(p1);
}

HLSL:

Returns the bitwise OR of all the values of <expr> across all active non-helper lanes in the current wave, and replicates it back to all active non-helper lanes.

Syntax

<int_type> WaveActiveBitOr(
   <int_type> expr
);

Parameters

expr

The expression to evaluate.

Return value

The bitwise OR value.

Remarks

This function is supported from shader model 6.0 in all shader stages.

 

See also

Overview of Shader Model 6

Shader Model 6

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