Optimize "constant_string".Length #2099
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```csharp
static int Test() => "Hello".Length; // replace with just `5`
```
Before:
```asm
movabs rax,0x7fd6c1758160
mov eax,DWORD PTR [rax]
ret
```
Now:
```asm
mov eax,0x5
ret
```
Also, handles cases after inlining, e.g.:
```csharp
bool Validate(string str)
{
return str.Length > 0 && str.Length <= 100;
}
bool Test()
{
return Validate("Hello"); // Validate() will be inlined
}
```
New codegen for `Test`:
```asm
mov eax, 1 ; return true
ret
```
I have a similar PR for CoreCLR: dotnet#1378
jit-diff report found >30k bytes of improvements.
|
@EgorBo, @akoeplinger, what's the best way to make forward progress on some of these mirrored mono PRs that haven't been touched in a while? e.g. in this case the Mono PR hasn't been updated in a month and a half. Thanks. |
|
let me close it, it was just a draft in mono/mono |
ghost
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!! This PR is a copy of mono/mono#16898, please do not edit or review it in this repo !!
!! Merge the PR only after the original PR is merged !!
```csharp
static int Test() => "Hello".Length; // replace with just
5Now:
Also, handles cases after inlining, e.g.:
New codegen for
Test:I have a similar PR for CoreCLR: #1378
jit-diff report found >30k bytes of improvements.