#!amber # Copyright 2020 Google LLC # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # A test for a bug found by the GraphicsFuzz project. # Short description: A fragment shader with recurrent always false if statement # The test passes because the shader always writes color red. # Optimized using spirv-opt with the following arguments: # '--vector-dce' # '--vector-dce' # '--scalar-replacement=100' # '--redundancy-elimination' # '--redundancy-elimination' # '--eliminate-dead-branches' # '--eliminate-dead-branches' # '--merge-blocks' # '--scalar-replacement=100' # '--reduce-load-size' # '--copy-propagate-arrays' # '--eliminate-dead-branches' # '--merge-blocks' # '--eliminate-dead-code-aggressive' # '--inline-entry-points-exhaustive' # '--simplify-instructions' # '--redundancy-elimination' # '--ccp' # '--eliminate-local-single-block' # '--scalar-replacement=100' # '--reduce-load-size' # '--eliminate-local-single-block' # '--reduce-load-size' # '--eliminate-local-single-store' # '--inline-entry-points-exhaustive' # spirv-opt commit hash: 230f363e6da32791f640b02205e0645cc67c3f1d SHADER vertex variant_vertex_shader PASSTHROUGH # variant_fragment_shader is derived from the following GLSL: # #version 320 es # precision highp float; # # precision highp int; # # # layout(location = 0) out vec4 _GLF_color; # # layout(set = 0, binding = 0) uniform buf0 # { # vec2 injectionSwitch; // x == 0.0, y == 1.0 # }; # void main() # { # const int loop_limit = 100; # int loop_count = 0; # // Always false. # if (injectionSwitch.x > injectionSwitch.y) # { # return; # } # // Always false. # gl_FragCoord.x < log(1.0); # for (; loop_count < loop_limit; loop_count++) # { # // Always false. # if (injectionSwitch.x > injectionSwitch.y) # { # break; # } # // Always false. # if (injectionSwitch.x > injectionSwitch.y) # { # _GLF_color = vec4(1.0); # } # else # { # // Always false. # if (gl_FragCoord.x < 0.0) # { # return; # } # } # // Always false. # if (injectionSwitch.x > injectionSwitch.y) # { # _GLF_color = vec4(1.0); # } # else # { # _GLF_color = vec4(1.0, 0.0, 0.0, 1.0); # } # // Always false. # if (injectionSwitch.x > injectionSwitch.y) # { # return; # } # // Always false. # if (gl_FragCoord.x < 0.0) # { # for (; loop_count < loop_limit; loop_count++) # { # } # } # } # if(loop_count >= loop_limit) # { # _GLF_color = vec4(1.0, 0.0, 0.0, 1.0); # } # else # { # _GLF_color = vec4(1.0); # } # } SHADER fragment variant_fragment_shader SPIRV-ASM TARGET_ENV spv1.0 ; SPIR-V ; Version: 1.0 ; Generator: Khronos Glslang Reference Front End; 10 ; Bound: 109 ; Schema: 0 OpCapability Shader %1 = OpExtInstImport "GLSL.std.450" OpMemoryModel Logical GLSL450 OpEntryPoint Fragment %4 "main" %30 %60 OpExecutionMode %4 OriginUpperLeft OpSource ESSL 320 OpName %4 "main" OpName %8 "loop_count" OpName %12 "buf0" OpMemberName %12 0 "injectionSwitch" OpName %14 "" OpName %30 "gl_FragCoord" OpName %60 "_GLF_color" OpMemberDecorate %12 0 Offset 0 OpDecorate %12 Block OpDecorate %14 DescriptorSet 0 OpDecorate %14 Binding 0 OpDecorate %30 BuiltIn FragCoord OpDecorate %60 Location 0 %2 = OpTypeVoid %3 = OpTypeFunction %2 %6 = OpTypeInt 32 1 %7 = OpTypePointer Function %6 %9 = OpConstant %6 0 %10 = OpTypeFloat 32 %11 = OpTypeVector %10 2 %12 = OpTypeStruct %11 %13 = OpTypePointer Uniform %12 %14 = OpVariable %13 Uniform %15 = OpTypeInt 32 0 %16 = OpConstant %15 0 %17 = OpTypePointer Uniform %10 %20 = OpConstant %15 1 %23 = OpTypeBool %28 = OpTypeVector %10 4 %29 = OpTypePointer Input %28 %30 = OpVariable %29 Input %31 = OpTypePointer Input %10 %34 = OpConstant %10 0 %42 = OpConstant %6 100 %59 = OpTypePointer Output %28 %60 = OpVariable %59 Output %61 = OpConstant %10 1 %62 = OpConstantComposite %28 %61 %61 %61 %61 %78 = OpConstantComposite %28 %61 %34 %34 %61 %100 = OpConstant %6 1 %4 = OpFunction %2 None %3 %5 = OpLabel %8 = OpVariable %7 Function OpStore %8 %9 %18 = OpAccessChain %17 %14 %9 %16 %19 = OpLoad %10 %18 %21 = OpAccessChain %17 %14 %9 %20 %22 = OpLoad %10 %21 %24 = OpFOrdGreaterThan %23 %19 %22 OpSelectionMerge %26 None OpBranchConditional %24 %25 %26 %25 = OpLabel OpReturn %26 = OpLabel %32 = OpAccessChain %31 %30 %16 %33 = OpLoad %10 %32 %35 = OpFOrdLessThan %23 %33 %34 OpBranch %36 %36 = OpLabel %41 = OpLoad %6 %8 %43 = OpSLessThan %23 %41 %42 OpLoopMerge %38 %39 None OpBranchConditional %43 %37 %38 %37 = OpLabel OpSelectionMerge %50 None OpBranchConditional %24 %49 %50 %49 = OpLabel OpBranch %38 %50 = OpLabel OpSelectionMerge %58 None OpBranchConditional %24 %57 %63 %57 = OpLabel OpStore %60 %62 OpBranch %58 %63 = OpLabel OpSelectionMerge %68 None OpBranchConditional %35 %67 %68 %67 = OpLabel OpReturn %68 = OpLabel OpBranch %58 %58 = OpLabel OpSelectionMerge %76 None OpBranchConditional %24 %75 %77 %75 = OpLabel OpStore %60 %62 OpBranch %76 %77 = OpLabel OpStore %60 %78 OpBranch %76 %76 = OpLabel OpSelectionMerge %85 None OpBranchConditional %24 %84 %85 %84 = OpLabel OpReturn %85 = OpLabel OpSelectionMerge %91 None OpBranchConditional %35 %90 %91 %90 = OpLabel OpBranch %92 %92 = OpLabel %97 = OpLoad %6 %8 %98 = OpSLessThan %23 %97 %42 OpLoopMerge %94 %93 None OpBranchConditional %98 %93 %94 %93 = OpLabel %99 = OpLoad %6 %8 %101 = OpIAdd %6 %99 %100 OpStore %8 %101 OpBranch %92 %94 = OpLabel OpBranch %91 %91 = OpLabel OpBranch %39 %39 = OpLabel %102 = OpLoad %6 %8 %103 = OpIAdd %6 %102 %100 OpStore %8 %103 OpBranch %36 %38 = OpLabel %104 = OpLoad %6 %8 %105 = OpSGreaterThanEqual %23 %104 %42 OpSelectionMerge %107 None OpBranchConditional %105 %106 %108 %106 = OpLabel OpStore %60 %78 OpBranch %107 %108 = OpLabel OpStore %60 %62 OpBranch %107 %107 = OpLabel OpReturn OpFunctionEnd END # uniforms for variant # injectionSwitch BUFFER variant_injectionSwitch DATA_TYPE vec2 STD140 DATA 0.0 1.0 END BUFFER variant_framebuffer FORMAT B8G8R8A8_UNORM PIPELINE graphics variant_pipeline ATTACH variant_vertex_shader ATTACH variant_fragment_shader FRAMEBUFFER_SIZE 16 16 BIND BUFFER variant_framebuffer AS color LOCATION 0 BIND BUFFER variant_injectionSwitch AS uniform DESCRIPTOR_SET 0 BINDING 0 END CLEAR_COLOR variant_pipeline 0 0 0 255 CLEAR variant_pipeline RUN variant_pipeline DRAW_RECT POS 0 0 SIZE 16 16 EXPECT variant_framebuffer IDX 0 0 SIZE 16 16 EQ_RGBA 255 0 0 255