Support writing to storage images with packed formats

shaderStorageImageWriteWithoutFormat will allow OpImageWrite to write to
images with packed formats.

Note we already claimed VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT and
VK_FORMAT_FEATURE_STORAGE_TEXEL_BUFFER_BIT support for these formats,
but without shaderStorageImageWriteWithoutFormat or
shaderStorageImageReadWithoutFormat they could neither be read nor
written since the spec states that if "The SPIR-V Image Format is not
compatible with the image view’s format", "the value of the texel
returned is undefined." and compatibility is defined as a strict 1:1
mapping.

Bug: b/203730083
Change-Id: I530780f955caefc8a7324f2ab8e05a503f2c20ef
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/59570
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>

src/Pipeline/SpirvShaderImage.cpp

diff --git a/src/Pipeline/SpirvShaderImage.cpp b/src/Pipeline/SpirvShaderImage.cpp
index 58642e2..a85c615 100644
--- a/src/Pipeline/SpirvShaderImage.cpp
+++ b/src/Pipeline/SpirvShaderImage.cpp
@@ -1155,12 +1155,14 @@
 		packed[0] = texel.Int(0);
 		break;
 	case VK_FORMAT_R8G8B8A8_UNORM:
+	case VK_FORMAT_A8B8G8R8_UNORM_PACK32:
 		packed[0] = (SIMD::UInt(Round(Min(Max(texel.Float(0), SIMD::Float(0.0f)), SIMD::Float(1.0f)) * SIMD::Float(255.0f)))) |
 		            ((SIMD::UInt(Round(Min(Max(texel.Float(1), SIMD::Float(0.0f)), SIMD::Float(1.0f)) * SIMD::Float(255.0f)))) << 8) |
 		            ((SIMD::UInt(Round(Min(Max(texel.Float(2), SIMD::Float(0.0f)), SIMD::Float(1.0f)) * SIMD::Float(255.0f)))) << 16) |
 		            ((SIMD::UInt(Round(Min(Max(texel.Float(3), SIMD::Float(0.0f)), SIMD::Float(1.0f)) * SIMD::Float(255.0f)))) << 24);
 		break;
 	case VK_FORMAT_R8G8B8A8_SNORM:
+	case VK_FORMAT_A8B8G8R8_SNORM_PACK32:
 		packed[0] = (SIMD::Int(Round(Min(Max(texel.Float(0), SIMD::Float(-1.0f)), SIMD::Float(1.0f)) * SIMD::Float(127.0f))) &
 		             SIMD::Int(0xFF)) |
 		            ((SIMD::Int(Round(Min(Max(texel.Float(1), SIMD::Float(-1.0f)), SIMD::Float(1.0f)) * SIMD::Float(127.0f))) &
@@ -1175,6 +1177,8 @@
 		break;
 	case VK_FORMAT_R8G8B8A8_SINT:
 	case VK_FORMAT_R8G8B8A8_UINT:
+	case VK_FORMAT_A8B8G8R8_SINT_PACK32:
+	case VK_FORMAT_A8B8G8R8_UINT_PACK32:
 		packed[0] = (SIMD::UInt(texel.UInt(0) & SIMD::UInt(0xff))) |
 		            (SIMD::UInt(texel.UInt(1) & SIMD::UInt(0xff)) << 8) |
 		            (SIMD::UInt(texel.UInt(2) & SIMD::UInt(0xff)) << 16) |

src/Vulkan/VkPhysicalDevice.cpp

diff --git a/src/Vulkan/VkPhysicalDevice.cpp b/src/Vulkan/VkPhysicalDevice.cpp
index bd05a84..df16133 100644
--- a/src/Vulkan/VkPhysicalDevice.cpp
+++ b/src/Vulkan/VkPhysicalDevice.cpp
@@ -1438,7 +1438,6 @@
 	case VK_FORMAT_R8_UINT:
 		pFormatProperties->optimalTilingFeatures |=
 		    VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT;
-		// [[fallthrough]]
 		pFormatProperties->bufferFeatures |=
 		    VK_FORMAT_FEATURE_STORAGE_TEXEL_BUFFER_BIT;
 		break;