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| author | ameerj <52414509+ameerj@users.noreply.github.com> | 2021-12-24 20:00:28 -0500 |
|---|---|---|
| committer | ameerj <52414509+ameerj@users.noreply.github.com> | 2021-12-29 19:03:49 -0500 |
| commit | 14ac0c2923c41df9c6fc4833d2a8e46a6efe5b59 (patch) | |
| tree | 6d9cb0ebd7d8d7b75d88a0d598c659b06d45004c /src/shader_recompiler/ir_opt/constant_propagation_pass.cpp | |
| parent | 640fc1418b08449f2ba729588aef5e06bc5df636 (diff) | |
shader: Add integer attribute get optimization pass
Works around an nvidia driver bug, where casting the integer attributes to float and back to an integer always returned 0.
Diffstat (limited to 'src/shader_recompiler/ir_opt/constant_propagation_pass.cpp')
| -rw-r--r-- | src/shader_recompiler/ir_opt/constant_propagation_pass.cpp | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp b/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp index d089fdd12f..c134a12bc6 100644 --- a/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp +++ b/src/shader_recompiler/ir_opt/constant_propagation_pass.cpp @@ -505,6 +505,29 @@ void FoldBitCast(IR::Inst& inst, IR::Opcode reverse) { return; } } + if constexpr (op == IR::Opcode::BitCastU32F32) { + // Workaround for new NVIDIA driver bug, where: + // uint attr = ftou(itof(gl_InstanceID)); + // always returned 0. + // We can instead manually optimize this and work around the driver bug: + // uint attr = uint(gl_InstanceID); + if (arg_inst->GetOpcode() == IR::Opcode::GetAttribute) { + const IR::Attribute attr{arg_inst->Arg(0).Attribute()}; + switch (attr) { + case IR::Attribute::PrimitiveId: + case IR::Attribute::InstanceId: + case IR::Attribute::VertexId: + break; + default: + return; + } + // Replace the bitcasts with an integer attribute get + inst.ReplaceOpcode(IR::Opcode::GetAttributeU32); + inst.SetArg(0, arg_inst->Arg(0)); + inst.SetArg(1, arg_inst->Arg(1)); + return; + } + } } void FoldInverseFunc(IR::Inst& inst, IR::Opcode reverse) { |