diff options
| author | gdkchan <gab.dark.100@gmail.com> | 2019-12-24 17:52:16 -0300 |
|---|---|---|
| committer | Thog <thog@protonmail.com> | 2020-01-09 02:13:00 +0100 |
| commit | a718b60d06f5ad2219d5896c7739c29444560811 (patch) | |
| tree | 50d895d9ebb9e34eefb874995e14f940556459bc /Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs | |
| parent | 82957fa96b1657d72290d721da370bf133dc7a8d (diff) | |
Fix exception on shader translator when adding goto temp variable
Diffstat (limited to 'Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs')
| -rw-r--r-- | Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs b/Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs index 55958a12..f2af84f3 100644 --- a/Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs +++ b/Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs @@ -78,13 +78,19 @@ namespace Ryujinx.Graphics.Shader.StructuredIr foreach (BasicBlock predecessor in block.Predecessors.OrderByDescending(x => x.Index)) { + // If not a loop, break. if (predecessor.Index < block.Index) { break; } + // Check if we can create a do-while loop here (only possible if the loop end + // falls inside the current scope), if not add a goto instead. if (predecessor.Index < _currEndIndex && !done) { + // Create do-while loop block. We must avoid inserting a goto at the end + // of the loop later, when the tail block is processed. So we add the predecessor + // to a list of loop tails to prevent it from being processed later. Operation branchOp = (Operation)predecessor.GetLastOp(); NewBlock(AstBlockType.DoWhile, branchOp, predecessor.Index + 1); @@ -95,6 +101,9 @@ namespace Ryujinx.Graphics.Shader.StructuredIr } else { + // Failed to create loop. Since this block is the loop head, we reset the + // goto condition variable here. The variable is always reset on the jump + // target, and this block is the jump target for some loop. AddGotoTempReset(block, GetGotoTempAsg(block.Index)); break; @@ -129,6 +138,8 @@ namespace Ryujinx.Graphics.Shader.StructuredIr { AstAssignment gotoTempAsg = GetGotoTempAsg(block.Branch.Index); + // We use DoWhile type here, as the condition should be true for + // unconditional branches, or it should jump if the condition is true otherwise. IAstNode cond = GetBranchCond(AstBlockType.DoWhile, branchOp); AddNode(Assign(gotoTempAsg.Destination, cond)); @@ -161,6 +172,12 @@ namespace Ryujinx.Graphics.Shader.StructuredIr private void AddGotoTempReset(BasicBlock block, AstAssignment gotoTempAsg) { + // If it was already added, we don't need to add it again. + if (gotoTempAsg.Parent != null) + { + return; + } + AddNode(gotoTempAsg); // For block 0, we don't need to add the extra "reset" at the beginning, @@ -200,6 +217,9 @@ namespace Ryujinx.Graphics.Shader.StructuredIr if (branchOp.Inst == Instruction.Branch) { + // If the branch is not conditional, the condition is a constant. + // For if it's false (always jump over, if block never executed). + // For loops it's always true (always loop). cond = Const(type == AstBlockType.If ? IrConsts.False : IrConsts.True); } else |