commit 5815e125f6e9a8fcec6dd66db8bd263de2474b9c
author Nicolas Capens <capn@google.com> Fri Dec 01 14:40:50 2017 -0500
committer Nicolas Capens <nicolascapens@google.com> Fri Dec 01 21:25:38 2017 +0000
tree a1bec6553d3d4372dbda9e3f0f634e3aea738695
parent 48280a4e92c9960cbb501e0ded86f662a03f9ad2

Move draw call early-outs until after validation.

Drawing without a current program is not an error and we can early-out,
but not until after other validation which could generate an error has
completed. Validation happening on a valid program happens afterwards
though. Likewise, providing insufficient vertices for even one
primitive results in drawing nothing, but validation still needs to
happen.

Change-Id: I5385ffe352fc38343caa41eb99f5549472da3b4f
Reviewed-on: https://swiftshader-review.googlesource.com/14489
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>

src/OpenGL/libGLESv2/Context.cpp

diff --git a/src/OpenGL/libGLESv2/Context.cpp b/src/OpenGL/libGLESv2/Context.cpp
index b32e792..8dec865 100644
--- a/src/OpenGL/libGLESv2/Context.cpp
+++ b/src/OpenGL/libGLESv2/Context.cpp
@@ -3481,21 +3481,13 @@
 
 void Context::drawArrays(GLenum mode, GLint first, GLsizei count, GLsizei instanceCount)
 {
-	if(!mState.currentProgram)
-	{
-		return;
-	}
-
 	sw::DrawType primitiveType;
 	int primitiveCount;
 	int verticesPerPrimitive;
 
 	if(!es2sw::ConvertPrimitiveType(mode, count, GL_NONE, primitiveType, primitiveCount, verticesPerPrimitive))
-		return error(GL_INVALID_ENUM);
-
-	if(primitiveCount <= 0)
 	{
-		return;
+		return error(GL_INVALID_ENUM);
 	}
 
 	if(!applyRenderTarget())
@@ -3515,6 +3507,11 @@
 			return error(err);
 		}
 
+		if(!mState.currentProgram)
+		{
+			return;
+		}
+
 		applyShaders();
 		applyTextures();
 
@@ -3523,6 +3520,11 @@
 			return error(GL_INVALID_OPERATION);
 		}
 
+		if(primitiveCount <= 0)
+		{
+			return;
+		}
+
 		TransformFeedback* transformFeedback = getTransformFeedback();
 		if(!cullSkipsDraw(mode) || (transformFeedback->isActive() && !transformFeedback->isPaused()))
 		{
@@ -3537,11 +3539,6 @@
 
 void Context::drawElements(GLenum mode, GLuint start, GLuint end, GLsizei count, GLenum type, const void *indices, GLsizei instanceCount)
 {
-	if(!mState.currentProgram)
-	{
-		return;
-	}
-
 	if(!indices && !getCurrentVertexArray()->getElementArrayBuffer())
 	{
 		return error(GL_INVALID_OPERATION);
@@ -3570,11 +3567,8 @@
 	int verticesPerPrimitive;
 
 	if(!es2sw::ConvertPrimitiveType(internalMode, count, type, primitiveType, primitiveCount, verticesPerPrimitive))
-		return error(GL_INVALID_ENUM);
-
-	if(primitiveCount <= 0)
 	{
-		return;
+		return error(GL_INVALID_ENUM);
 	}
 
 	if(!applyRenderTarget())
@@ -3602,6 +3596,11 @@
 			return error(err);
 		}
 
+		if(!mState.currentProgram)
+		{
+			return;
+		}
+
 		applyShaders();
 		applyTextures();
 
@@ -3610,6 +3609,11 @@
 			return error(GL_INVALID_OPERATION);
 		}
 
+		if(primitiveCount <= 0)
+		{
+			return;
+		}
+
 		TransformFeedback* transformFeedback = getTransformFeedback();
 		if(!cullSkipsDraw(internalMode) || (transformFeedback->isActive() && !transformFeedback->isPaused()))
 		{