--- /dev/null
+#!amber
+
+# Copyright 2019 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 GraphicsFuzz.
+
+# Short description: A fragment shader with a do while that always returns
+
+# The test passes because the shader always writes the color red. The do while returns on first iteration.
+
+# Optimized using spirv-opt with the following arguments:
+# '--redundancy-elimination'
+# '--reduce-load-size'
+# '--combine-access-chains'
+# '--eliminate-dead-code-aggressive'
+# '--eliminate-dead-branches'
+# spirv-opt commit hash: 06407250a169c6a03b3765e86619075af1a8c187
+
+
+
+SHADER vertex variant_vertex_shader PASSTHROUGH
+
+# variant_fragment_shader is derived from the following GLSL:
+# #version 310 es
+# precision highp float;
+#
+# layout(location = 0) out vec4 _GLF_color;
+#
+# struct _GLF_struct_12
+# {
+# int count;
+# };
+#
+# bool puzzlelize(vec2 pos)
+# {
+# return true;
+# }
+#
+# void main()
+# {
+# _GLF_color = vec4(1.0, 0.0, 0.0, 1.0);
+#
+# vec2 grid;
+# _GLF_struct_12 _GLF_struct_replacement_12;
+#
+# do
+# {
+# if (gl_FragCoord.y > -1.0) // Always true
+# {
+# return;
+# }
+# } while (_GLF_struct_replacement_12.count != 1);
+#
+# grid += vec2(1, _GLF_struct_replacement_12.count);
+# vec2 position;
+# position = grid;
+# vec4(puzzlelize(position));
+#
+# _GLF_color = vec4(1.0, 1.0, 1.0, 1.0); // This should not be reached
+# }
+SHADER fragment variant_fragment_shader SPIRV-ASM
+; SPIR-V
+; Version: 1.0
+; Generator: Khronos Glslang Reference Front End; 7
+; Bound: 64
+; Schema: 0
+ OpCapability Shader
+ %1 = OpExtInstImport "GLSL.std.450"
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Fragment %4 "main" %19 %28
+ OpExecutionMode %4 OriginUpperLeft
+ OpSource ESSL 310
+ OpName %4 "main"
+ OpName %12 "puzzlelize(vf2;"
+ OpName %11 "pos"
+ OpName %19 "_GLF_color"
+ OpName %28 "gl_FragCoord"
+ OpName %40 "_GLF_struct_12"
+ OpMemberName %40 0 "count"
+ OpName %42 "_GLF_struct_replacement_12"
+ OpName %49 "grid"
+ OpName %56 "position"
+ OpName %58 "param"
+ OpDecorate %19 Location 0
+ OpDecorate %28 BuiltIn FragCoord
+ OpMemberDecorate %40 0 RelaxedPrecision
+ OpDecorate %46 RelaxedPrecision
+ OpDecorate %51 RelaxedPrecision
+ %2 = OpTypeVoid
+ %3 = OpTypeFunction %2
+ %6 = OpTypeFloat 32
+ %7 = OpTypeVector %6 2
+ %8 = OpTypePointer Function %7
+ %9 = OpTypeBool
+ %10 = OpTypeFunction %9 %8
+ %14 = OpConstantTrue %9
+ %17 = OpTypeVector %6 4
+ %18 = OpTypePointer Output %17
+ %19 = OpVariable %18 Output
+ %20 = OpConstant %6 1
+ %21 = OpConstant %6 0
+ %22 = OpConstantComposite %17 %20 %21 %21 %20
+ %27 = OpTypePointer Input %17
+ %28 = OpVariable %27 Input
+ %29 = OpTypeInt 32 0
+ %30 = OpConstant %29 1
+ %31 = OpTypePointer Input %6
+ %34 = OpConstant %6 -1
+ %39 = OpTypeInt 32 1
+ %40 = OpTypeStruct %39
+ %41 = OpTypePointer Function %40
+ %43 = OpConstant %39 0
+ %44 = OpTypePointer Function %39
+ %47 = OpConstant %39 1
+ %63 = OpConstantComposite %17 %20 %20 %20 %20
+ %4 = OpFunction %2 None %3
+ %5 = OpLabel
+ %42 = OpVariable %41 Function
+ %49 = OpVariable %8 Function
+ %56 = OpVariable %8 Function
+ %58 = OpVariable %8 Function
+ OpStore %19 %22
+ OpBranch %23
+ %23 = OpLabel
+ OpLoopMerge %25 %26 None
+ OpBranch %24
+ %24 = OpLabel
+ %32 = OpAccessChain %31 %28 %30
+ %33 = OpLoad %6 %32
+ %35 = OpFOrdGreaterThan %9 %33 %34
+ OpSelectionMerge %37 None
+ OpBranchConditional %35 %36 %37
+ %36 = OpLabel
+ OpReturn
+ %37 = OpLabel
+ OpBranch %26
+ %26 = OpLabel
+ %45 = OpAccessChain %44 %42 %43
+ %46 = OpLoad %39 %45
+ %48 = OpINotEqual %9 %46 %47
+ OpBranchConditional %48 %23 %25
+ %25 = OpLabel
+ %51 = OpLoad %39 %45
+ %52 = OpConvertSToF %6 %51
+ %53 = OpCompositeConstruct %7 %20 %52
+ %54 = OpLoad %7 %49
+ %55 = OpFAdd %7 %54 %53
+ OpStore %49 %55
+ %57 = OpLoad %7 %49
+ OpStore %56 %57
+ %59 = OpLoad %7 %56
+ OpStore %58 %59
+ %60 = OpFunctionCall %9 %12 %58
+ OpStore %19 %63
+ OpReturn
+ OpFunctionEnd
+ %12 = OpFunction %9 None %10
+ %11 = OpFunctionParameter %8
+ %13 = OpLabel
+ OpReturnValue %14
+ OpFunctionEnd
+END
+
+# uniforms for variant
+
+
+BUFFER variant_framebuffer FORMAT B8G8R8A8_UNORM
+
+PIPELINE graphics variant_pipeline
+ ATTACH variant_vertex_shader
+ ATTACH variant_fragment_shader
+ FRAMEBUFFER_SIZE 256 256
+ BIND BUFFER variant_framebuffer AS color LOCATION 0
+END
+CLEAR_COLOR variant_pipeline 0 0 0 255
+
+CLEAR variant_pipeline
+RUN variant_pipeline DRAW_RECT POS 0 0 SIZE 256 256
+
+EXPECT variant_framebuffer IDX 0 0 SIZE 256 256 EQ_RGBA 255 0 0 255