Make CPU coverage bot a bit faster

Adding -O1 and reducing the shards to cut down on overhead
in post-production.  This seems to save us a few minutes
(e.g. ~26 -> ~23 minutes).

The optimized code has about 600 fewer reachable lines of code
(according to the Coverage measurement), which is acceptable
given our tests run on -O1 or better.

Experiments (in this review) show that O3 is faster than O1, 
but not significantly enough where we want to deviate from 
our normal Debug bots:
Control: 73 minutes
-O1: 59 minutes
-O2: 60 minutes
-O3: 50 minutes

Bug: skia:
NOTRY=true
Change-Id: I33344c1cd2408373004d010e36ce27d6aa03deb2
Reviewed-on: https://skia-review.googlesource.com/65503
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Kevin Lubick <kjlubick@google.com>

6 files changed, 45 insertions, 243 deletions

diff --git a/infra/bots/jobs.json b/infra/bots/jobs.json
index 35e7ae809e..12102b1b5f 100644
--- a/infra/bots/jobs.json
+++ b/infra/bots/jobs.json
@@ -349,7 +349,7 @@
   "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-SK_USE_DISCARDABLE_SCALEDIMAGECACHE",
   "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-SafeStack",
   "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-UBSAN_float_cast_overflow",
-  "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_16-Coverage",
+  "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_12-Coverage",
   "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Release-All",
   "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Release-All-ASAN",
   "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Release-All-Fast",
diff --git a/infra/bots/recipe_modules/flavor/examples/full.expected/Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-Coverage.json b/infra/bots/recipe_modules/flavor/examples/full.expected/Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-Coverage.json
index 0b86e2b99e..07cdd71d53 100644
--- a/infra/bots/recipe_modules/flavor/examples/full.expected/Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-Coverage.json
+++ b/infra/bots/recipe_modules/flavor/examples/full.expected/Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-Coverage.json
@@ -20,7 +20,7 @@
       "[START_DIR]/skia/bin/gn",
       "gen",
       "[START_DIR]/out/Debug",
-      "--args=cc=\"[START_DIR]/clang_linux/bin/clang\" cxx=\"[START_DIR]/clang_linux/bin/clang++\" extra_cflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] extra_ldflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fuse-ld=lld\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] skia_use_system_freetype2=false"
+      "--args=cc=\"[START_DIR]/clang_linux/bin/clang\" cxx=\"[START_DIR]/clang_linux/bin/clang++\" extra_cflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\", \"-O1\"] extra_ldflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fuse-ld=lld\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"]"
     ],
     "cwd": "[START_DIR]/skia",
     "env": {
diff --git a/infra/bots/recipe_modules/flavor/gn_flavor.py b/infra/bots/recipe_modules/flavor/gn_flavor.py
index aca8880a53..6c8a3a2282 100644
--- a/infra/bots/recipe_modules/flavor/gn_flavor.py
+++ b/infra/bots/recipe_modules/flavor/gn_flavor.py
@@ -67,7 +67,7 @@ class GNFlavorUtils(default_flavor.DefaultFlavorUtils):
       extra_ldflags.append('-fprofile-instr-generate')
       extra_ldflags.append('-fcoverage-mapping')
 
-    elif compiler != 'MSVC' and configuration == 'Debug':
+    if compiler != 'MSVC' and configuration == 'Debug':
       extra_cflags.append('-O1')
 
     if extra_config == 'Exceptions':
@@ -134,8 +134,6 @@ class GNFlavorUtils(default_flavor.DefaultFlavorUtils):
         'skia_use_icu':        'false',
         'skia_enable_gpu':     'false',
       })
-    if 'Coverage' in extra_config:
-      args['skia_use_system_freetype2'] = 'false'
 
     sanitize = ''
     if extra_config == 'UBSAN_float_cast_overflow':
diff --git a/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Debug-Coverage.json b/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Debug-Coverage.json
index caa4d2cf1f..15496bee0a 100644
--- a/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Debug-Coverage.json
+++ b/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Debug-Coverage.json
@@ -114,7 +114,7 @@
       "[CUSTOM_/_B_WORK]/skia/bin/gn",
       "gen",
       "[CUSTOM_/_B_WORK]/skia/out/Build-Debian9-Clang-x86_64-Debug-Coverage/Debug",
-      "--args=cc=\"[START_DIR]/clang_linux/bin/clang\" cxx=\"[START_DIR]/clang_linux/bin/clang++\" extra_cflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] extra_ldflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fuse-ld=lld\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] skia_use_system_freetype2=false target_cpu=\"x86_64\""
+      "--args=cc=\"[START_DIR]/clang_linux/bin/clang\" cxx=\"[START_DIR]/clang_linux/bin/clang++\" extra_cflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\", \"-O1\"] extra_ldflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fuse-ld=lld\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] target_cpu=\"x86_64\""
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",
     "env": {
diff --git a/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Release-Vulkan_Coverage.json b/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Release-Vulkan_Coverage.json
index 71f8195017..46fb64d6de 100644
--- a/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Release-Vulkan_Coverage.json
+++ b/infra/bots/recipes/compile.expected/Build-Debian9-Clang-x86_64-Release-Vulkan_Coverage.json
@@ -114,7 +114,7 @@
       "[CUSTOM_/_B_WORK]/skia/bin/gn",
       "gen",
       "[CUSTOM_/_B_WORK]/skia/out/Build-Debian9-Clang-x86_64-Release-Vulkan_Coverage/Release",
-      "--args=cc=\"[START_DIR]/clang_linux/bin/clang\" cxx=\"[START_DIR]/clang_linux/bin/clang++\" extra_cflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] extra_ldflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fuse-ld=lld\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] is_debug=false skia_enable_vulkan_debug_layers=false skia_use_system_freetype2=false skia_vulkan_sdk=\"[START_DIR]/linux_vulkan_sdk\" target_cpu=\"x86_64\""
+      "--args=cc=\"[START_DIR]/clang_linux/bin/clang\" cxx=\"[START_DIR]/clang_linux/bin/clang++\" extra_cflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] extra_ldflags=[\"-B[START_DIR]/clang_linux/bin\", \"-fuse-ld=lld\", \"-fprofile-instr-generate\", \"-fcoverage-mapping\"] is_debug=false skia_enable_vulkan_debug_layers=false skia_vulkan_sdk=\"[START_DIR]/linux_vulkan_sdk\" target_cpu=\"x86_64\""
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",
     "env": {
diff --git a/infra/bots/tasks.json b/infra/bots/tasks.json
index a448a786bf..6bc2c76a81 100644
--- a/infra/bots/tasks.json
+++ b/infra/bots/tasks.json
@@ -2109,10 +2109,10 @@
         "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-UBSAN_float_cast_overflow"
       ]
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_12-Coverage": {
       "priority": 0.8,
       "tasks": [
-        "Upload-Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_16-Coverage"
+        "Upload-Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_12-Coverage"
       ]
     },
     "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Release-All": {
@@ -16156,7 +16156,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_00_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_00_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16191,7 +16191,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_00_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_00_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16204,7 +16204,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_01_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_01_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16239,7 +16239,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_01_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_01_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16252,7 +16252,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_02_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_02_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16287,7 +16287,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_02_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_02_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16300,7 +16300,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_03_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_03_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16335,7 +16335,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_03_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_03_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16348,7 +16348,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_04_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_04_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16383,7 +16383,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_04_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_04_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16396,7 +16396,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_05_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_05_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16431,7 +16431,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_05_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_05_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16444,7 +16444,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_06_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_06_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16479,7 +16479,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_06_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_06_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16492,7 +16492,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_07_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_07_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16527,7 +16527,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_07_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_07_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16540,7 +16540,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_08_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_08_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16575,7 +16575,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_08_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_08_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16588,7 +16588,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_09_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_09_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16623,7 +16623,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_09_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_09_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16636,7 +16636,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_10_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_10_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16671,7 +16671,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_10_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_10_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -16684,7 +16684,7 @@
       "max_attempts": 1,
       "priority": 0.8
     },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_11_16-Coverage": {
+    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_11_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
@@ -16719,199 +16719,7 @@
         "../../..",
         "test",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_11_16-Coverage",
-        "swarm_out_dir=${ISOLATED_OUTDIR}",
-        "revision=<(REVISION)",
-        "patch_repo=<(PATCH_REPO)",
-        "patch_storage=<(PATCH_STORAGE)",
-        "patch_issue=<(ISSUE)",
-        "patch_set=<(PATCHSET)"
-      ],
-      "io_timeout_ns": 2400000000000,
-      "isolate": "test_skia_bundled_unix.isolate",
-      "max_attempts": 1,
-      "priority": 0.8
-    },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_12_16-Coverage": {
-      "cipd_packages": [
-        {
-          "name": "skia/bots/skimage",
-          "path": "skimage",
-          "version": "version:32"
-        },
-        {
-          "name": "skia/bots/skp",
-          "path": "skp",
-          "version": "version:92"
-        },
-        {
-          "name": "skia/bots/svg",
-          "path": "svg",
-          "version": "version:9"
-        }
-      ],
-      "dependencies": [
-        "Build-Debian9-Clang-x86_64-Debug-Coverage",
-        "Housekeeper-PerCommit-BundleRecipes"
-      ],
-      "dimensions": [
-        "cpu:x86-64-Haswell_GCE",
-        "gpu:none",
-        "os:Debian-9.1",
-        "pool:Skia"
-      ],
-      "execution_timeout_ns": 14400000000000,
-      "expiration_ns": 72000000000000,
-      "extra_args": [
-        "--workdir",
-        "../../..",
-        "test",
-        "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_12_16-Coverage",
-        "swarm_out_dir=${ISOLATED_OUTDIR}",
-        "revision=<(REVISION)",
-        "patch_repo=<(PATCH_REPO)",
-        "patch_storage=<(PATCH_STORAGE)",
-        "patch_issue=<(ISSUE)",
-        "patch_set=<(PATCHSET)"
-      ],
-      "io_timeout_ns": 2400000000000,
-      "isolate": "test_skia_bundled_unix.isolate",
-      "max_attempts": 1,
-      "priority": 0.8
-    },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_13_16-Coverage": {
-      "cipd_packages": [
-        {
-          "name": "skia/bots/skimage",
-          "path": "skimage",
-          "version": "version:32"
-        },
-        {
-          "name": "skia/bots/skp",
-          "path": "skp",
-          "version": "version:92"
-        },
-        {
-          "name": "skia/bots/svg",
-          "path": "svg",
-          "version": "version:9"
-        }
-      ],
-      "dependencies": [
-        "Build-Debian9-Clang-x86_64-Debug-Coverage",
-        "Housekeeper-PerCommit-BundleRecipes"
-      ],
-      "dimensions": [
-        "cpu:x86-64-Haswell_GCE",
-        "gpu:none",
-        "os:Debian-9.1",
-        "pool:Skia"
-      ],
-      "execution_timeout_ns": 14400000000000,
-      "expiration_ns": 72000000000000,
-      "extra_args": [
-        "--workdir",
-        "../../..",
-        "test",
-        "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_13_16-Coverage",
-        "swarm_out_dir=${ISOLATED_OUTDIR}",
-        "revision=<(REVISION)",
-        "patch_repo=<(PATCH_REPO)",
-        "patch_storage=<(PATCH_STORAGE)",
-        "patch_issue=<(ISSUE)",
-        "patch_set=<(PATCHSET)"
-      ],
-      "io_timeout_ns": 2400000000000,
-      "isolate": "test_skia_bundled_unix.isolate",
-      "max_attempts": 1,
-      "priority": 0.8
-    },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_14_16-Coverage": {
-      "cipd_packages": [
-        {
-          "name": "skia/bots/skimage",
-          "path": "skimage",
-          "version": "version:32"
-        },
-        {
-          "name": "skia/bots/skp",
-          "path": "skp",
-          "version": "version:92"
-        },
-        {
-          "name": "skia/bots/svg",
-          "path": "svg",
-          "version": "version:9"
-        }
-      ],
-      "dependencies": [
-        "Build-Debian9-Clang-x86_64-Debug-Coverage",
-        "Housekeeper-PerCommit-BundleRecipes"
-      ],
-      "dimensions": [
-        "cpu:x86-64-Haswell_GCE",
-        "gpu:none",
-        "os:Debian-9.1",
-        "pool:Skia"
-      ],
-      "execution_timeout_ns": 14400000000000,
-      "expiration_ns": 72000000000000,
-      "extra_args": [
-        "--workdir",
-        "../../..",
-        "test",
-        "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_14_16-Coverage",
-        "swarm_out_dir=${ISOLATED_OUTDIR}",
-        "revision=<(REVISION)",
-        "patch_repo=<(PATCH_REPO)",
-        "patch_storage=<(PATCH_STORAGE)",
-        "patch_issue=<(ISSUE)",
-        "patch_set=<(PATCHSET)"
-      ],
-      "io_timeout_ns": 2400000000000,
-      "isolate": "test_skia_bundled_unix.isolate",
-      "max_attempts": 1,
-      "priority": 0.8
-    },
-    "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_15_16-Coverage": {
-      "cipd_packages": [
-        {
-          "name": "skia/bots/skimage",
-          "path": "skimage",
-          "version": "version:32"
-        },
-        {
-          "name": "skia/bots/skp",
-          "path": "skp",
-          "version": "version:92"
-        },
-        {
-          "name": "skia/bots/svg",
-          "path": "svg",
-          "version": "version:9"
-        }
-      ],
-      "dependencies": [
-        "Build-Debian9-Clang-x86_64-Debug-Coverage",
-        "Housekeeper-PerCommit-BundleRecipes"
-      ],
-      "dimensions": [
-        "cpu:x86-64-Haswell_GCE",
-        "gpu:none",
-        "os:Debian-9.1",
-        "pool:Skia"
-      ],
-      "execution_timeout_ns": 14400000000000,
-      "expiration_ns": 72000000000000,
-      "extra_args": [
-        "--workdir",
-        "../../..",
-        "test",
-        "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_15_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_11_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",
@@ -27359,7 +27167,7 @@
       "isolate": "upload_dm_results.isolate",
       "priority": 0.8
     },
-    "Upload-Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_16-Coverage": {
+    "Upload-Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_12-Coverage": {
       "cipd_packages": [
         {
           "name": "skia/bots/clang_linux",
@@ -27368,22 +27176,18 @@
         }
       ],
       "dependencies": [
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_00_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_01_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_02_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_03_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_04_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_05_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_06_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_07_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_08_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_09_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_10_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_11_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_12_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_13_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_14_16-Coverage",
-        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_15_16-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_00_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_01_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_02_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_03_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_04_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_05_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_06_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_07_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_08_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_09_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_10_12-Coverage",
+        "Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-shard_11_12-Coverage",
         "Build-Debian9-Clang-x86_64-Debug-Coverage"
       ],
       "dimensions": [
@@ -27397,7 +27201,7 @@
         "../../..",
         "upload_coverage_results",
         "repository=<(REPO)",
-        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_16-Coverage",
+        "buildername=Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-Shard_12-Coverage",
         "swarm_out_dir=${ISOLATED_OUTDIR}",
         "revision=<(REVISION)",
         "patch_repo=<(PATCH_REPO)",