#!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: Code wrapped in nested single iteration loops

# The test passes because the first return statement in 'f' is guaranteed to be hit on the first loop iteration, so that red is written to the framebuffer

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;
#
# vec3 f()
# {
#  int iteration = 0;
#  for(
#      int k = 0;
#      k < 100;
#      k ++
#  )
#   {
#    iteration ++;
#   }
#  if(iteration < 100)
#   {
#    return vec3(1.0, float(iteration - 1), float(iteration - 1));
#   }
#  else
#   {
#    do
#     {
#      do
#       {
#        return vec3(1.0, 0.0, 0.0);
#       }
#      while(false);
#     }
#    while(false);
#   }
# }
# void main()
# {
#  _GLF_color = vec4(f(), 1.0);
# }
SHADER fragment variant_fragment_shader SPIRV-ASM
; SPIR-V
; Version: 1.0
; Generator: Khronos Glslang Reference Front End; 8
; Bound: 65
; Schema: 0
               OpCapability Shader
          %1 = OpExtInstImport "GLSL.std.450"
               OpMemoryModel Logical GLSL450
               OpEntryPoint Fragment %4 "main" %59
               OpExecutionMode %4 OriginUpperLeft
               OpSource ESSL 310
               OpName %4 "main"
               OpName %9 "f("
               OpName %13 "iteration"
               OpName %15 "k"
               OpName %59 "_GLF_color"
               OpDecorate %13 RelaxedPrecision
               OpDecorate %15 RelaxedPrecision
               OpDecorate %21 RelaxedPrecision
               OpDecorate %25 RelaxedPrecision
               OpDecorate %27 RelaxedPrecision
               OpDecorate %28 RelaxedPrecision
               OpDecorate %29 RelaxedPrecision
               OpDecorate %30 RelaxedPrecision
               OpDecorate %35 RelaxedPrecision
               OpDecorate %36 RelaxedPrecision
               OpDecorate %38 RelaxedPrecision
               OpDecorate %39 RelaxedPrecision
               OpDecorate %59 Location 0
          %2 = OpTypeVoid
          %3 = OpTypeFunction %2
          %6 = OpTypeFloat 32
          %7 = OpTypeVector %6 3
          %8 = OpTypeFunction %7
         %11 = OpTypeInt 32 1
         %12 = OpTypePointer Function %11
         %14 = OpConstant %11 0
         %22 = OpConstant %11 100
         %23 = OpTypeBool
         %26 = OpConstant %11 1
         %34 = OpConstant %6 1
         %52 = OpConstant %6 0
         %53 = OpConstantComposite %7 %34 %52 %52
         %55 = OpConstantFalse %23
         %57 = OpTypeVector %6 4
         %58 = OpTypePointer Output %57
         %59 = OpVariable %58 Output
          %4 = OpFunction %2 None %3
          %5 = OpLabel
         %60 = OpFunctionCall %7 %9
         %61 = OpCompositeExtract %6 %60 0
         %62 = OpCompositeExtract %6 %60 1
         %63 = OpCompositeExtract %6 %60 2
         %64 = OpCompositeConstruct %57 %61 %62 %63 %34
               OpStore %59 %64
               OpReturn
               OpFunctionEnd
          %9 = OpFunction %7 None %8
         %10 = OpLabel
         %13 = OpVariable %12 Function
         %15 = OpVariable %12 Function
               OpStore %13 %14
               OpStore %15 %14
               OpBranch %16
         %16 = OpLabel
               OpLoopMerge %18 %19 None
               OpBranch %20
         %20 = OpLabel
         %21 = OpLoad %11 %15
         %24 = OpSLessThan %23 %21 %22
               OpBranchConditional %24 %17 %18
         %17 = OpLabel
         %25 = OpLoad %11 %13
         %27 = OpIAdd %11 %25 %26
               OpStore %13 %27
               OpBranch %19
         %19 = OpLabel
         %28 = OpLoad %11 %15
         %29 = OpIAdd %11 %28 %26
               OpStore %15 %29
               OpBranch %16
         %18 = OpLabel
         %30 = OpLoad %11 %13
         %31 = OpSLessThan %23 %30 %22
               OpSelectionMerge %33 None
               OpBranchConditional %31 %32 %43
         %32 = OpLabel
         %35 = OpLoad %11 %13
         %36 = OpISub %11 %35 %26
         %37 = OpConvertSToF %6 %36
         %38 = OpLoad %11 %13
         %39 = OpISub %11 %38 %26
         %40 = OpConvertSToF %6 %39
         %41 = OpCompositeConstruct %7 %34 %37 %40
               OpReturnValue %41
         %43 = OpLabel
               OpBranch %44
         %44 = OpLabel
               OpLoopMerge %46 %47 None
               OpBranch %45
         %45 = OpLabel
               OpBranch %48
         %48 = OpLabel
               OpLoopMerge %50 %51 None
               OpBranch %49
         %49 = OpLabel
               OpReturnValue %53
         %51 = OpLabel
               OpBranch %48
         %50 = OpLabel
               OpUnreachable
         %47 = OpLabel
               OpBranch %44
         %46 = OpLabel
               OpUnreachable
         %33 = OpLabel
               OpUnreachable
               OpFunctionEnd
END


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