layers: Fix minor completeness/performance issue

The first time the condition is discovered it will
be the same as every subsequent time, so there is
no need to continue. Also, the whole structure must
be compared, so memcmp assures that will happen
with good efficiency

Change-Id: I71f608c71f83ebcd02212bb391a30bdf15279ff6

1 files changed, 6 insertions, 8 deletions

diff --git a/layers/core_validation.cpp b/layers/core_validation.cpp
index 9211503f..4ca938fe 100644
--- a/layers/core_validation.cpp
+++ b/layers/core_validation.cpp
@@ -3093,18 +3093,16 @@ static bool verifyPipelineCreateState(layer_data *my_data, const VkDevice device
             if (pPipeline->attachments.size() > 1) {
                 VkPipelineColorBlendAttachmentState *pAttachments = &pPipeline->attachments[0];
                 for (size_t i = 1; i < pPipeline->attachments.size(); i++) {
-                    if ((pAttachments[0].blendEnable != pAttachments[i].blendEnable) ||
-                        (pAttachments[0].srcColorBlendFactor != pAttachments[i].srcColorBlendFactor) ||
-                        (pAttachments[0].dstColorBlendFactor != pAttachments[i].dstColorBlendFactor) ||
-                        (pAttachments[0].colorBlendOp != pAttachments[i].colorBlendOp) ||
-                        (pAttachments[0].srcAlphaBlendFactor != pAttachments[i].srcAlphaBlendFactor) ||
-                        (pAttachments[0].dstAlphaBlendFactor != pAttachments[i].dstAlphaBlendFactor) ||
-                        (pAttachments[0].alphaBlendOp != pAttachments[i].alphaBlendOp) ||
-                        (pAttachments[0].colorWriteMask != pAttachments[i].colorWriteMask)) {
+                    // Quoting the spec: "If [the independent blend] feature is not enabled, the VkPipelineColorBlendAttachmentState
+                    // settings for all color attachments must be identical." VkPipelineColorBlendAttachmentState contains
+                    // only attachment state, so memcmp is best suited for the comparison
+                    if (memcmp(static_cast<const void *>(pAttachments), static_cast<const void *>(&pAttachments[i]),
+                               sizeof(pAttachments[0]))) {
                         skip_call |= log_msg(my_data->report_data, VK_DEBUG_REPORT_ERROR_BIT_EXT, (VkDebugReportObjectTypeEXT)0, 0,
                                              __LINE__, DRAWSTATE_INDEPENDENT_BLEND, "DS",
                                              "Invalid Pipeline CreateInfo: If independent blend feature not "
                                              "enabled, all elements of pAttachments must be identical");
+                        break;
                     }
                 }
             }