From 2e0a9f66a0d41dd81bfaa7078aad9b53bedb547e Mon Sep 17 00:00:00 2001
From: Subv <subv2112@gmail.com>
Date: Fri, 20 Apr 2018 09:02:28 -0500
Subject: [PATCH] ShaderGen: Ignore the 'sched' instruction when generating
shaders.
The 'sched' instruction has a very convoluted encoding, but fortunately it seems to only appear on a fixed interval (once every 4 instructions).
---
.../renderer_opengl/gl_shader_decompiler.cpp | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/src/video_core/renderer_opengl/gl_shader_decompiler.cpp b/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
index de137558d0..c23f590cd8 100644
--- a/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
+++ b/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
@@ -276,6 +276,18 @@ private:
shader.AddLine(dest + " = " + src + ";");
}
+ /*
+ * Returns whether the instruction at the specified offset is a 'sched' instruction.
+ * Sched instructions always appear before a sequence of 3 instructions.
+ */
+ bool IsSchedInstruction(u32 offset) const {
+ // sched instructions appear once every 4 instructions.
+ static constexpr size_t SchedPeriod = 4;
+ u32 absolute_offset = offset - main_offset;
+
+ return (absolute_offset % SchedPeriod) == 0;
+ }
+
/**
* Compiles a single instruction from Tegra to GLSL.
* @param offset the offset of the Tegra shader instruction.
@@ -283,6 +295,10 @@ private:
* + 1. If the current instruction always terminates the program, returns PROGRAM_END.
*/
u32 CompileInstr(u32 offset) {
+ // Ignore sched instructions when generating code.
+ if (IsSchedInstruction(offset))
+ return offset + 1;
+
const Instruction instr = {program_code[offset]};
shader.AddLine("// " + std::to_string(offset) + ": " + OpCode::GetInfo(instr.opcode).name);