From 40a945f293e2cc1a6ed130777c973c5cbcde1059 Mon Sep 17 00:00:00 2001
From: Yuly Novikov <ynovikov@chromium.org>
Date: Thu, 1 Mar 2018 17:37:43 -0500
Subject: [PATCH] Rename vulkan_loader to libvulkan

Also add a build argument to build it as a shared library.

BUG=angleproject:2343

Change-Id: Ia590632b94d71b10d3ee64974fa4f5b4f00c3a70
Reviewed-on: https://chromium-review.googlesource.com/954403
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>
---
 BUILD.gn                                      |  3 +--
 doc/DebuggingTips.md                          | 11 +++++++++++
 gni/angle.gni                                 |  1 +
 third_party/vulkan-validation-layers/BUILD.gn |  8 +++++++-
 4 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/BUILD.gn b/BUILD.gn
index f0c233ec2..345f27d95 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -429,8 +429,7 @@ if (angle_enable_vulkan) {
       "$angle_root/third_party/vulkan-validation-layers:vulkan_config",
     ]
     if (!is_android) {
-      deps +=
-          [ "$angle_root/third_party/vulkan-validation-layers:vulkan_loader" ]
+      deps += [ "$angle_root/third_party/vulkan-validation-layers:libvulkan" ]
       data_deps += [ "$angle_root/third_party/vulkan-validation-layers:vulkan_gen_json_files" ]
       public_configs += [ "$angle_root/third_party/vulkan-validation-layers:vulkan_loader_config" ]
     }
diff --git a/doc/DebuggingTips.md b/doc/DebuggingTips.md
index 17b5d01de..793a1f8d8 100644
--- a/doc/DebuggingTips.md
+++ b/doc/DebuggingTips.md
@@ -24,3 +24,14 @@ export TRACE_LIBGL="/usr/lib/libGL.so.1" # may require a different path
 apitrace trace -o mytrace ./out/Debug/hello_triangle
 qapitrace mytrace
 ```
+
+## Running ANGLE under GAPID on Linux
+
+[GAPID](https://github.com/google/gapid) can be used to capture trace of Vulkan commands on Linux.
+For it to work, libvulkan has to be a shared library, instead of being statically linked into ANGLE, which is the default behavior.
+This is done with the gn arg:
+```
+angle_shared_libvulkan = true
+```
+
+When capturing traces of gtest based tests built inside Chromium checkout, make sure to run the tests with `--single-process-tests` argument.
\ No newline at end of file
diff --git a/gni/angle.gni b/gni/angle.gni
index 3bf2c94d2..c347602fc 100644
--- a/gni/angle.gni
+++ b/gni/angle.gni
@@ -31,6 +31,7 @@ declare_args() {
         (current_cpu == "arm" && android32_ndk_api_level >= 24) ||
         (current_cpu == "arm64" && android64_ndk_api_level >= 24)
   }
+  angle_shared_libvulkan = false
 }
 
 declare_args() {
diff --git a/third_party/vulkan-validation-layers/BUILD.gn b/third_party/vulkan-validation-layers/BUILD.gn
index c8ca7945b..d84a266b6 100644
--- a/third_party/vulkan-validation-layers/BUILD.gn
+++ b/third_party/vulkan-validation-layers/BUILD.gn
@@ -273,7 +273,13 @@ config("vulkan_loader_config") {
 }
 
 if (!is_android) {
-  static_library("vulkan_loader") {
+  if (angle_shared_libvulkan) {
+    library_type = "shared_library"
+  } else {
+    library_type = "static_library"
+  }
+
+  target(library_type, "libvulkan") {
     sources = [
       "src/loader/cJSON.c",
       "src/loader/cJSON.h",