fixed issue with SkSL dead code elimination

Bug: skia:6747
Change-Id: I8566f0f6822a452167079cca004730ec0db318a8
Reviewed-on: https://skia-review.googlesource.com/19275
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/tests/SkSLGLSLTest.cpp b/tests/SkSLGLSLTest.cpp
index 678ff13dd3..2ea6c7ec71 100644
--- a/tests/SkSLGLSLTest.cpp
+++ b/tests/SkSLGLSLTest.cpp
@@ -1375,4 +1375,22 @@ DEF_TEST(SkSLDependentInitializers, r) {
          "}\n");
 }
 
+DEF_TEST(SkSLDeadLoopVar, r) {
+    test(r,
+         "void main() {"
+         "for (int x = 0; x < 4; ) {"
+         "break;"
+         "}"
+         "}",
+         *SkSL::ShaderCapsFactory::Default(),
+         "#version 400\n"
+         "out vec4 sk_FragColor;\n"
+         "void main() {\n"
+         "    for (; true; ) {\n"
+         "        break;\n"
+         "    }\n"
+         "}\n"
+         );
+}
+
 #endif