Add 8-bit unorm support to the floating point version of writeColor

This CL adds support for 8-bit channels unorm formats to
the floating point version of writeColor.

Bug: b/204322086
Change-Id: I88d57757b8640ae73fdd721208c6e5662f6d0285
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/69770
Commit-Queue: Alexis Hétu <sugoi@google.com>
Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>

src/Pipeline/PixelRoutine.cpp

diff --git a/src/Pipeline/PixelRoutine.cpp b/src/Pipeline/PixelRoutine.cpp
index 0abe2c1..b6b98dc 100644
--- a/src/Pipeline/PixelRoutine.cpp
+++ b/src/Pipeline/PixelRoutine.cpp
@@ -2503,6 +2503,22 @@
 	vk::Format format = state.colorFormat[index];
 	switch(format)
 	{
+	case VK_FORMAT_B8G8R8A8_UNORM:
+	case VK_FORMAT_R8G8B8A8_UNORM:
+	case VK_FORMAT_A8B8G8R8_UNORM_PACK32:
+		color.w = Min(Max(color.w, 0.0f), 1.0f);  // TODO(b/204560089): Omit clamp if redundant
+		color.w = As<Float4>(RoundInt(color.w * 0xFF));
+		color.z = Min(Max(color.z, 0.0f), 1.0f);  // TODO(b/204560089): Omit clamp if redundant
+		color.z = As<Float4>(RoundInt(color.z * 0xFF));
+		// [[fallthrough]]
+	case VK_FORMAT_R8G8_UNORM:
+		color.y = Min(Max(color.y, 0.0f), 1.0f);  // TODO(b/204560089): Omit clamp if redundant
+		color.y = As<Float4>(RoundInt(color.y * 0xFF));
+		//[[fallthrough]]
+	case VK_FORMAT_R8_UNORM:
+		color.x = Min(Max(color.x, 0.0f), 1.0f);  // TODO(b/204560089): Omit clamp if redundant
+		color.x = As<Float4>(RoundInt(color.x * 0xFF));
+		break;
 	case VK_FORMAT_R16G16B16A16_UNORM:
 		color.w = Min(Max(color.w, 0.0f), 1.0f);  // TODO(b/204560089): Omit clamp if redundant
 		color.w = As<Float4>(RoundInt(color.w * 0xFFFF));
@@ -2546,6 +2562,7 @@
 	case VK_FORMAT_R16_UINT:
 	case VK_FORMAT_R8_SINT:
 	case VK_FORMAT_R8_UINT:
+	case VK_FORMAT_R8_UNORM:
 	case VK_FORMAT_A2B10G10R10_UINT_PACK32:
 	case VK_FORMAT_A2R10G10B10_UINT_PACK32:
 		break;
@@ -2558,6 +2575,7 @@
 	case VK_FORMAT_R16G16_UINT:
 	case VK_FORMAT_R8G8_SINT:
 	case VK_FORMAT_R8G8_UINT:
+	case VK_FORMAT_R8G8_UNORM:
 		color.z = color.x;
 		color.x = UnpackLow(color.x, color.y);
 		color.z = UnpackHigh(color.z, color.y);
@@ -2575,8 +2593,13 @@
 	case VK_FORMAT_R8G8B8A8_UINT:
 	case VK_FORMAT_A8B8G8R8_UINT_PACK32:
 	case VK_FORMAT_A8B8G8R8_SINT_PACK32:
+	case VK_FORMAT_R8G8B8A8_UNORM:
+	case VK_FORMAT_A8B8G8R8_UNORM_PACK32:
 		transpose4x4(color.x, color.y, color.z, color.w);
 		break;
+	case VK_FORMAT_B8G8R8A8_UNORM:
+		transpose4x4zyxw(color.z, color.y, color.x, color.w);
+		break;
 	default:
 		UNSUPPORTED("VkFormat: %d", int(format));
 	}
@@ -2697,6 +2720,7 @@
 		break;
 	case VK_FORMAT_R8_SINT:
 	case VK_FORMAT_R8_UINT:
+	case VK_FORMAT_R8_UNORM:
 		if(writeMask & 0x00000001)
 		{
 			buffer += x;
@@ -2831,6 +2855,7 @@
 		break;
 	case VK_FORMAT_R8G8_SINT:
 	case VK_FORMAT_R8G8_UINT:
+	case VK_FORMAT_R8G8_UNORM:
 		if((writeMask & 0x00000003) != 0x0)
 		{
 			buffer += 2 * x;
@@ -3039,10 +3064,15 @@
 			*Pointer<UInt4>(buffer) = (As<UInt4>(packedCol) & mergedMask) | (As<UInt4>(value) & ~mergedMask);
 		}
 		break;
+	case VK_FORMAT_B8G8R8A8_UNORM:
+		writeMask = (writeMask & 0x0000000A) | (writeMask & 0x00000001) << 2 | (writeMask & 0x00000004) >> 2;
+		// [[fallthrough]]
 	case VK_FORMAT_R8G8B8A8_SINT:
 	case VK_FORMAT_R8G8B8A8_UINT:
 	case VK_FORMAT_A8B8G8R8_UINT_PACK32:
 	case VK_FORMAT_A8B8G8R8_SINT_PACK32:
+	case VK_FORMAT_R8G8B8A8_UNORM:
+	case VK_FORMAT_A8B8G8R8_UNORM_PACK32:
 		if((writeMask & 0x0000000F) != 0x0)
 		{
 			UInt2 value, packedCol, mergedMask;