d2c6967f1d
Essentially, instead of having the inlined UntypedFunction::Create(f)
return an UntypedFunction which is then passed as an argument to
non-inlined RoboCallerReceivers::AddReceiverImpl(), we let
UntypedFunction::PrepareArgs(f) return a few different kinds of
trivial structs (depending on what sort of type f has) which are
passed as arguments to non-inlined RoboCallerReceivers::AddReceiver()
(which then converts them to UntypedFunction by calling
UntypedFunction::Create()). These structs are smaller than
UntypedFunction and optimized for argument passing, so many fewer
instructions are needed.
Example code:
struct Foo {
void Receive(int, float, int, float);
void TestAddLambdaReceiver();
webrtc::RoboCaller<int, float, int, float> rc;
};
void Foo::TestAddLambdaReceiver() {
rc.AddReceiver([this](int a, float b, int c, float d){
Receive(a, b, c, d);});
}
On arm32, we get before this CL:
Foo::TestAddLambdaReceiver():
push {r11, lr}
mov r11, sp
sub sp, sp, #24
ldr r1, .LCPI0_0
mov r2, #0
stm sp, {r0, r2}
add r1, pc, r1
str r2, [sp, #20]
str r1, [sp, #16]
mov r1, sp
bl RoboCallerReceivers::AddReceiverImpl
mov sp, r11
pop {r11, pc}
.LCPI0_0:
.long CallInlineStorage<Foo::TestAddLambdaReceiver()::$_0>
CallInlineStorage<Foo::TestAddLambdaReceiver()::$_0>:
ldr r0, [r0]
b Foo::Receive(int, float, int, float)
After this CL:
Foo::TestAddLambdaReceiver():
ldr r3, .LCPI0_0
mov r2, r0
add r3, pc, r3
b RoboCallerReceivers::AddReceiver<1u>
.LCPI0_0:
.long CallInlineStorage<Foo::TestAddLambdaReceiver()::$_0>
CallInlineStorage<Foo::TestAddLambdaReceiver()::$_0>:
ldr r0, [r0]
b Foo::Receive(int, float, int, float)
(Symbol names abbreviated so that they'll fit on one line.)
So a reduction from 64 to 28 bytes. The improvements on arm64 and
x86_64 are similar.
Bug: webrtc:11943
Change-Id: I93fbba083be0235051c3279d3e3f6852a4a9fdad
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/185960
Commit-Queue: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#32244}
WebRTC is a free, open software project that provides browsers and mobile applications with Real-Time Communications (RTC) capabilities via simple APIs. The WebRTC components have been optimized to best serve this purpose.
Our mission: To enable rich, high-quality RTC applications to be developed for the browser, mobile platforms, and IoT devices, and allow them all to communicate via a common set of protocols.
The WebRTC initiative is a project supported by Google, Mozilla and Opera, amongst others.
Development
See here for instructions on how to get started developing with the native code.
Authoritative list of directories that contain the native API header files.
More info
- Official web site: http://www.webrtc.org
- Master source code repo: https://webrtc.googlesource.com/src
- Samples and reference apps: https://github.com/webrtc
- Mailing list: http://groups.google.com/group/discuss-webrtc
- Continuous build: http://build.chromium.org/p/client.webrtc
- Coding style guide
- Code of conduct