OpenGL: Fix switch with only a default case.
The compiler would produce an `OPCODE_ELSE` with no preceeding `OPCODE_IF`, causing hilarity downstream in the VertexProgram and PixelProgram.
Credit to Dan Sinclair who did all the hard work here.
Bug: None - surfaced when rolling a new version of SPIR-V cross.
Change-Id: I8a937a4d24768dbcc125c3fff834342bd8d0ef29
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/40832
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Tested-by: Ben Clayton <bclayton@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
diff --git a/src/OpenGL/compiler/OutputASM.cpp b/src/OpenGL/compiler/OutputASM.cpp
index 8d82eca..9e9d885 100644
--- a/src/OpenGL/compiler/OutputASM.cpp
+++ b/src/OpenGL/compiler/OutputASM.cpp
@@ -2058,7 +2058,11 @@
// If there's a default case, traverse it here
if(defaultIt != sequence.end())
{
- emit(sw::Shader::OPCODE_ELSE);
+ if(nbCases != 0)
+ {
+ emit(sw::Shader::OPCODE_ELSE);
+ }
+
for(++defaultIt; defaultIt != sequence.end(); ++defaultIt)
{
(*defaultIt)->traverse(this);
diff --git a/tests/GLESUnitTests/unittests.cpp b/tests/GLESUnitTests/unittests.cpp
index ee9693e..92987c6 100644
--- a/tests/GLESUnitTests/unittests.cpp
+++ b/tests/GLESUnitTests/unittests.cpp
@@ -2066,6 +2066,18 @@
float F (float f) { return G(-m); })");
}
+TEST_F(SwiftShaderTest, SwitchDefaultOnly)
+{
+ checkCompiles(R"(
+ float F (float f) {
+ switch (0u) {
+ default:
+ return -f;
+ }
+ return f;
+ })");
+}
+
#ifndef EGL_ANGLE_iosurface_client_buffer
# define EGL_ANGLE_iosurface_client_buffer 1
# define EGL_IOSURFACE_ANGLE 0x3454
