From 7e03dc7f6347fa7a780a4d144466b43e3ed2094e Mon Sep 17 00:00:00 2001
From: Austin Eng <enga@chromium.org>
Date: Thu, 28 Apr 2022 22:27:53 +0000
Subject: [PATCH] Fix 64 to 32 bit narrowing in dawn/utils

Bug: dawn:1377
Change-Id: Iece057afeeca43092e5e16d7f00d2388dde31d13
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/87673
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
---
 src/dawn/common/Numeric.h      | 11 +++++++++++
 src/dawn/utils/WGPUHelpers.cpp |  3 ++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/dawn/common/Numeric.h b/src/dawn/common/Numeric.h
index f8e559599e..a9a4521fc9 100644
--- a/src/dawn/common/Numeric.h
+++ b/src/dawn/common/Numeric.h
@@ -16,6 +16,9 @@
 #define SRC_DAWN_COMMON_NUMERIC_H_
 
 #include <limits>
+#include <type_traits>
+
+#include "dawn/common/Assert.h"
 
 namespace detail {
 
@@ -39,4 +42,12 @@ inline constexpr uint32_t u32_sizeof = detail::u32_sizeof<T>();
 template <typename T>
 inline constexpr uint32_t u32_alignof = detail::u32_alignof<T>();
 
+// Only defined for unsigned integers because that is all that is
+// needed at the time of writing.
+template <typename Dst, typename Src, typename = std::enable_if_t<std::is_unsigned_v<Src>>>
+inline Dst checked_cast(const Src& value) {
+    ASSERT(value <= std::numeric_limits<Dst>::max());
+    return static_cast<Dst>(value);
+}
+
 #endif  // SRC_DAWN_COMMON_NUMERIC_H_
diff --git a/src/dawn/utils/WGPUHelpers.cpp b/src/dawn/utils/WGPUHelpers.cpp
index 7c36d81428..52e070af3b 100644
--- a/src/dawn/utils/WGPUHelpers.cpp
+++ b/src/dawn/utils/WGPUHelpers.cpp
@@ -22,6 +22,7 @@
 
 #include "dawn/common/Constants.h"
 #include "dawn/common/Log.h"
+#include "dawn/common/Numeric.h"
 
 #include "spirv-tools/optimizer.hpp"
 
@@ -382,7 +383,7 @@ namespace utils {
 
         wgpu::BindGroupDescriptor descriptor;
         descriptor.layout = layout;
-        descriptor.entryCount = entries.size();
+        descriptor.entryCount = checked_cast<uint32_t>(entries.size());
         descriptor.entries = entries.data();
 
         return device.CreateBindGroup(&descriptor);