sksl support for static ifs & switches

Bug: skia:
Change-Id: Ic9e01a3a18efddb19bab26e92bfb473cad294fc1
Reviewed-on: https://skia-review.googlesource.com/16144
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Ben Wagner <benjaminwagner@google.com>

3 files changed, 193 insertions, 24 deletions

diff --git a/tests/SkSLErrorTest.cpp b/tests/SkSLErrorTest.cpp
index d443b1844f..453a8f84c9 100644
--- a/tests/SkSLErrorTest.cpp
+++ b/tests/SkSLErrorTest.cpp
@@ -16,12 +16,7 @@ static void test_failure(skiatest::Reporter* r, const char* src, const char* err
     SkSL::Program::Settings settings;
     sk_sp<GrShaderCaps> caps = SkSL::ShaderCapsFactory::Default();
     settings.fCaps = caps.get();
-    std::unique_ptr<SkSL::Program> program = compiler.convertProgram(SkSL::Program::kFragment_Kind,
-                                                                     SkString(src), settings);
-    if (program) {
-        SkSL::String ignored;
-        compiler.toSPIRV(*program, &ignored);
-    }
+    compiler.convertProgram(SkSL::Program::kFragment_Kind, SkString(src), settings);
     SkSL::String skError(error);
     if (compiler.errorText() != skError) {
         SkDebugf("SKSL ERROR:\n    source: %s\n    expected: %s    received: %s", src, error,
@@ -38,8 +33,6 @@ static void test_success(skiatest::Reporter* r, const char* src) {
     std::unique_ptr<SkSL::Program> program = compiler.convertProgram(SkSL::Program::kFragment_Kind,
                                                                      SkString(src), settings);
     REPORTER_ASSERT(r, program);
-    SkSL::String ignored;
-    REPORTER_ASSERT(r, compiler.toSPIRV(*program, &ignored));
 }
 
 DEF_TEST(SkSLUndefinedSymbol, r) {
@@ -405,15 +398,6 @@ DEF_TEST(SkSLBadCap, r) {
                  "error: 1: unknown capability flag 'bugFreeDriver'\n1 error\n");
 }
 
-DEF_TEST(SkSLBadOffset, r) {
-    test_failure(r,
-                 "struct Bad { layout (offset = 5) int x; } bad; void main() { bad.x = 5; }",
-                 "error: 1: offset of field 'x' must be a multiple of 4\n1 error\n");
-    test_failure(r,
-                 "struct Bad { int x; layout (offset = 0) int y; } bad; void main() { bad.x = 5; }",
-                 "error: 1: offset of field 'y' must be at least 4\n1 error\n");
-}
-
 DEF_TEST(SkSLDivByZero, r) {
     test_failure(r,
                  "int x = 1 / 0;",
@@ -466,4 +450,43 @@ DEF_TEST(SkSLFieldAfterRuntimeArray, r) {
                  "array\n1 error\n");
 }
 
+DEF_TEST(SkSLStaticIf, r) {
+    test_success(r,
+                 "void main() { float x = 5; float y = 10;"
+                 "@if (x < y) { sk_FragColor = vec4(1); } }");
+    test_failure(r,
+                 "void main() { float x = sqrt(25); float y = 10;"
+                 "@if (x < y) { sk_FragColor = vec4(1); } }",
+                 "error: 1: static if has non-static test\n1 error\n");
+}
+
+DEF_TEST(SkSLStaticSwitch, r) {
+    test_success(r,
+                 "void main() {"
+                 "int x = 1;"
+                 "@switch (x) {"
+                 "case 1: sk_FragColor = vec4(1); break;"
+                 "default: sk_FragColor = vec4(0);"
+                 "}"
+                 "}");
+    test_failure(r,
+                 "void main() {"
+                 "int x = int(sqrt(1));"
+                 "@switch (x) {"
+                 "case 1: sk_FragColor = vec4(1); break;"
+                 "default: sk_FragColor = vec4(0);"
+                 "}"
+                 "}",
+                 "error: 1: static switch has non-static test\n1 error\n");
+    test_failure(r,
+                 "void main() {"
+                 "int x = 1;"
+                 "@switch (x) {"
+                 "case 1: sk_FragColor = vec4(1); if (sqrt(0) < sqrt(1)) break;"
+                 "default: sk_FragColor = vec4(0);"
+                 "}"
+                 "}",
+                 "error: 1: static switch contains non-static conditional break\n1 error\n");
+}
+
 #endif
diff --git a/tests/SkSLGLSLTest.cpp b/tests/SkSLGLSLTest.cpp
index 32fd668dda..ff1d5f5972 100644
--- a/tests/SkSLGLSLTest.cpp
+++ b/tests/SkSLGLSLTest.cpp
@@ -831,7 +831,7 @@ DEF_TEST(SkSLMatFolding, r) {
          "}\n");
 }
 
-DEF_TEST(SkSLStaticIf, r) {
+DEF_TEST(SkSLConstantIf, r) {
     test(r,
          "void main() {"
          "int x;"
@@ -1067,10 +1067,11 @@ DEF_TEST(SkSLGeometry, r) {
 }
 
 DEF_TEST(SkSLSwitch, r) {
+    // basic "does a switch even work" test
     test(r,
          "void main() {"
          "    float x;"
-         "    switch (1) {"
+         "    switch (int(sqrt(1))) {"
          "        case 0:"
          "            x = 0.0;"
          "            break;"
@@ -1087,7 +1088,7 @@ DEF_TEST(SkSLSwitch, r) {
          "out vec4 sk_FragColor;\n"
          "void main() {\n"
          "    float x;\n"
-         "    switch (1) {\n"
+         "    switch (int(sqrt(1.0))) {\n"
          "        case 0:\n"
          "            x = 0.0;\n"
          "            break;\n"
@@ -1099,10 +1100,11 @@ DEF_TEST(SkSLSwitch, r) {
          "    }\n"
          "    sk_FragColor = vec4(x);\n"
          "}\n");
+    // dead code inside of switch
     test(r,
          "void main() {"
          "    float x;"
-         "    switch (2) {"
+         "    switch (int(sqrt(2))) {"
          "        case 0:"
          "            x = 0.0;"
          "        case 1:"
@@ -1116,7 +1118,7 @@ DEF_TEST(SkSLSwitch, r) {
          "#version 400\n"
          "out vec4 sk_FragColor;\n"
          "void main() {\n"
-         "    switch (2) {\n"
+         "    switch (int(sqrt(2.0))) {\n"
          "        case 0:\n"
          "            ;\n"
          "        case 1:\n"
@@ -1126,12 +1128,113 @@ DEF_TEST(SkSLSwitch, r) {
          "    }\n"
          "    sk_FragColor = vec4(2.0);\n"
          "}\n");
+    // non-static test w/ fallthrough
+    test(r,
+         "void main() {"
+         "    float x = 0.0;"
+         "    switch (int(sqrt(3))) {"
+         "        case 0:"
+         "            x = 0.0;"
+         "        case 1:"
+         "            x = 1.0;"
+         "    }"
+         "    sk_FragColor = vec4(x);"
+         "}",
+         *SkSL::ShaderCapsFactory::Default(),
+         "#version 400\n"
+         "out vec4 sk_FragColor;\n"
+         "void main() {\n"
+         "    float x = 0.0;\n"
+         "    switch (int(sqrt(3.0))) {\n"
+         "        case 0:\n"
+         "            x = 0.0;\n"
+         "        case 1:\n"
+         "            x = 1.0;\n"
+         "    }\n"
+         "    sk_FragColor = vec4(x);\n"
+         "}\n");
+    // static test w/ fallthrough
+    test(r,
+         "void main() {"
+         "    float x = 0.0;"
+         "    switch (0) {"
+         "        case 0:"
+         "            x = 0.0;"
+         "        case 1:"
+         "            x = 1.0;"
+         "    }"
+         "    sk_FragColor = vec4(x);"
+         "}",
+         *SkSL::ShaderCapsFactory::Default(),
+         "#version 400\n"
+         "out vec4 sk_FragColor;\n"
+         "void main() {\n"
+         "    sk_FragColor = vec4(1.0);\n"
+         "}\n");
+    // static test w/ fallthrough, different entry point
+    test(r,
+         "void main() {"
+         "    float x = 0.0;"
+         "    switch (1) {"
+         "        case 0:"
+         "            x = 0.0;"
+         "        case 1:"
+         "            x = 1.0;"
+         "    }"
+         "    sk_FragColor = vec4(x);"
+         "}",
+         *SkSL::ShaderCapsFactory::Default(),
+         "#version 400\n"
+         "out vec4 sk_FragColor;\n"
+         "void main() {\n"
+         "    sk_FragColor = vec4(1.0);\n"
+         "}\n");
+    // static test w/ break
+    test(r,
+         "void main() {"
+         "    float x = 0.0;"
+         "    switch (0) {"
+         "        case 0:"
+         "            x = 0.0;"
+         "            break;"
+         "        case 1:"
+         "            x = 1.0;"
+         "    }"
+         "    sk_FragColor = vec4(x);"
+         "}",
+         *SkSL::ShaderCapsFactory::Default(),
+         "#version 400\n"
+         "out vec4 sk_FragColor;\n"
+         "void main() {\n"
+         "    sk_FragColor = vec4(0.0);\n"
+         "}\n");
+    // static test w/ static conditional break
+    test(r,
+         "void main() {"
+         "    float x = 0.0;"
+         "    switch (0) {"
+         "        case 0:"
+         "            x = 0.0;"
+         "            if (x < 1) break;"
+         "        case 1:"
+         "            x = 1.0;"
+         "    }"
+         "    sk_FragColor = vec4(x);"
+         "}",
+         *SkSL::ShaderCapsFactory::Default(),
+         "#version 400\n"
+         "out vec4 sk_FragColor;\n"
+         "void main() {\n"
+         "    sk_FragColor = vec4(0.0);\n"
+         "}\n");
+    // static test w/ non-static conditional break
     test(r,
          "void main() {"
          "    float x = 0.0;"
-         "    switch (3) {"
+         "    switch (0) {"
          "        case 0:"
          "            x = 0.0;"
+         "            if (x < sqrt(1)) break;"
          "        case 1:"
          "            x = 1.0;"
          "    }"
@@ -1142,9 +1245,10 @@ DEF_TEST(SkSLSwitch, r) {
          "out vec4 sk_FragColor;\n"
          "void main() {\n"
          "    float x = 0.0;\n"
-         "    switch (3) {\n"
+         "    switch (0) {\n"
          "        case 0:\n"
          "            x = 0.0;\n"
+         "            if (0.0 < sqrt(1.0)) break;\n"
          "        case 1:\n"
          "            x = 1.0;\n"
          "    }\n"
diff --git a/tests/SkSLSPIRVTest.cpp b/tests/SkSLSPIRVTest.cpp
new file mode 100644
index 0000000000..4d5457f339
--- /dev/null
+++ b/tests/SkSLSPIRVTest.cpp
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkSLCompiler.h"
+
+#include "Test.h"
+
+#if SK_SUPPORT_GPU
+
+static void test_failure(skiatest::Reporter* r, const char* src, const char* error) {
+    SkSL::Compiler compiler;
+    SkSL::Program::Settings settings;
+    sk_sp<GrShaderCaps> caps = SkSL::ShaderCapsFactory::Default();
+    settings.fCaps = caps.get();
+    std::unique_ptr<SkSL::Program> program = compiler.convertProgram(SkSL::Program::kFragment_Kind,
+                                                                     SkString(src), settings);
+    if (program) {
+        SkSL::String ignored;
+        compiler.toSPIRV(*program, &ignored);
+    }
+    SkSL::String skError(error);
+    if (compiler.errorText() != skError) {
+        SkDebugf("SKSL ERROR:\n    source: %s\n    expected: %s    received: %s", src, error,
+                 compiler.errorText().c_str());
+    }
+    REPORTER_ASSERT(r, compiler.errorText() == skError);
+}
+
+DEF_TEST(SkSLBadOffset, r) {
+    test_failure(r,
+                 "struct Bad { layout (offset = 5) int x; } bad; void main() { bad.x = 5; }",
+                 "error: 1: offset of field 'x' must be a multiple of 4\n1 error\n");
+    test_failure(r,
+                 "struct Bad { int x; layout (offset = 0) int y; } bad; void main() { bad.x = 5; }",
+                 "error: 1: offset of field 'y' must be at least 4\n1 error\n");
+}
+
+#endif