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swiftshader
Commit 1eb017d8 by Ben Clayton
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SpirvShader: Implement OpBitCount

Bug: b/126873455 Tests: dEQP-VK.glsl.builtin.function.integer.bitcount.* Change-Id: I2fa97f54a1ee68767fd13cafa3aeecfd7d068602 Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/28471Tested-by: 's avatarBen Clayton <bclayton@google.com> Reviewed-by: 's avatarChris Forbes <chrisforbes@google.com> Reviewed-by: 's avatarNicolas Capens <nicolascapens@google.com> Presubmit-Ready: Ben Clayton <bclayton@google.com> Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
parent 620f7089
Showing with 17 additions and 0 deletions
src/Pipeline/SpirvShader.cpp
......@@ -366,6 +366,7 @@ namespace sw
case spv::OpVectorExtractDynamic:
case spv::OpVectorInsertDynamic:
case spv::OpNot: // Unary ops
case spv::OpBitCount:
case spv::OpSNegate:
case spv::OpFNegate:
case spv::OpLogicalNot:
......@@ -1632,6 +1633,7 @@ namespace sw
return EmitTranspose(insn, state);
case spv::OpNot:
case spv::OpBitCount:
case spv::OpSNegate:
case spv::OpFNegate:
case spv::OpLogicalNot:
......@@ -2331,6 +2333,21 @@ namespace sw
case spv::OpLogicalNot: // logical not == bitwise not due to all-bits boolean representation
dst.move(i, ~src.UInt(i));
break;
case spv::OpBitCount:
{
// TODO: Add an intrinsic to reactor. Even if there isn't a
// single vector instruction, there may be target-dependent
// ways to make this faster.
// https://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel
auto v = src.UInt(i);
SIMD::UInt c = v - ((v >> 1) & SIMD::UInt(0x55555555));
c = ((c >> 2) & SIMD::UInt(0x33333333)) + (c & SIMD::UInt(0x33333333));
c = ((c >> 4) + c) & SIMD::UInt(0x0F0F0F0F);
c = ((c >> 8) + c) & SIMD::UInt(0x00FF00FF);
c = ((c >> 16) + c) & SIMD::UInt(0x0000FFFF);
dst.move(i, c);
break;
}
case spv::OpSNegate:
dst.move(i, -src.Int(i));
break;
......
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