Merge pull request #2899 from MicrosoftDocs/master

5/22 AM Publish

Author: Saisang

docs/build/arm64-exception-handling.md

@@ -301,12 +301,7 @@ The unwind codes are encoded according to the table below. All unwind codes are
 |`end`|            11100100: end of unwind code. Implies ret in epilog. |
 |`end_c`|        11100101: end of unwind code in current chained scope. |
 |`save_next`|        11100110: save next non-volatile Int or FP register pair. |
-|`arithmetic(add)`|    11100111'000zxxxx: add cookie reg(z) to lr (0=x28, 1=sp); `add lr, lr, reg(z)` |
-|`arithmetic(sub)`|    11100111'001zxxxx: sub cookie reg(z) from lr (0=x28, 1=sp); `sub lr, lr, reg(z)` |
-|`arithmetic(eor)`|    11100111'010zxxxx: eor lr with cookie reg(z) (0=x28, 1=sp); `eor lr, lr, reg(z)` |
-|`arithmetic(rol)`|    11100111'0110xxxx: simulated rol of lr with cookie reg (x28); xip0 = neg x28; `ror lr, xip0` |
-|`arithmetic(ror)`|    11100111'100zxxxx: ror lr with cookie reg(z) (0=x28, 1=sp); `ror lr, lr, reg(z)` |
-| |            11100111: xxxz----: ---- reserved |
+| |            11100111: reserved |
 | |              11101xxx: reserved for custom stack cases below only generated for asm routines |
 | |              11101000: Custom stack for MSFT_OP_TRAP_FRAME |
 | |              11101001: Custom stack for MSFT_OP_MACHINE_FRAME |

docs/cpp/thiscall.md

@@ -1,32 +1,28 @@
 ---
 title: "__thiscall"
-ms.date: "11/04/2016"
+ms.date: "05/22/2020"
 f1_keywords: ["__thiscall", "__thiscall_cpp"]
 helpviewer_keywords: ["__thiscall keyword [C++]"]
 ms.assetid: a6a22dd2-0101-4885-b33b-22f6057965df
 ---
-# __thiscall
+# `__thiscall`
 
-**Microsoft Specific**
+The **Microsoft-specific** **`__thiscall`** calling convention is used on C++ class member functions on the x86 architecture. It's the default calling convention used by member functions that don't use variable arguments (`vararg` functions).
 
-The **__thiscall** calling convention is used on member functions and is the default calling convention used by C++ member functions that do not use variable arguments. Under **__thiscall**, the callee cleans the stack, which is impossible for `vararg` functions. Arguments are pushed on the stack from right to left, with the **this** pointer being passed via register ECX, and not on the stack, on the x86 architecture.
+Under **`__thiscall`**, the callee cleans the stack, which is impossible for `vararg` functions. Arguments are pushed on the stack from right to left. The **`this`** pointer is passed via register ECX, and not on the stack.
 
-One reason to use **__thiscall** is in classes whose member functions use `__clrcall` by default. In that case, you can use **__thiscall** to make individual member functions callable from native code.
+On ARM, ARM64, and x64 machines, **`__thiscall`** is accepted and ignored by the compiler. That's because they use a register-based calling convention by default.
 
-When compiling with [/clr:pure](../build/reference/clr-common-language-runtime-compilation.md), all functions and function pointers are `__clrcall` unless specified otherwise. The **/clr:pure** and **/clr:safe** compiler options are deprecated in Visual Studio 2015 and unsupported in Visual Studio 2017.
+One reason to use **`__thiscall`** is in classes whose member functions use **`__clrcall`** by default. In that case, you can use **`__thiscall`** to make individual member functions callable from native code.
 
-In releases before Visual Studio 2005, the **__thiscall** calling convention could not be explicitly specified in a program, because **__thiscall** was not a keyword.
+When compiling with [**`/clr:pure`**](../build/reference/clr-common-language-runtime-compilation.md), all functions and function pointers are **`__clrcall`** unless specified otherwise. The **`/clr:pure`** and **`/clr:safe`** compiler options are deprecated in Visual Studio 2015 and unsupported in Visual Studio 2017.
 
-`vararg` member functions use the **__cdecl** calling convention. All function arguments are pushed on the stack, with the **this** pointer placed on the stack last
+`vararg` member functions use the **`__cdecl`** calling convention. All function arguments are pushed on the stack, with the **`this`** pointer placed on the stack last.
 
-Because this calling convention applies only to C++, there is no C name decoration scheme.
+Because this calling convention applies only to C++, it doesn't have a C name decoration scheme.
 
-On ARM and x64 machines, **__thiscall** is accepted and ignored by the compiler.
-
-For non-static class functions, if the function is defined out-of-line, the calling convention modifier does not have to be specified on the out-of-line definition. That is, for class non-static member methods, the calling convention specified during declaration is assumed at the point of definition.
-
-**END Microsoft Specific**
+When you define a non-static class member function out-of-line, specify the calling convention modifier only in the declaration. You don't have to specify it again on the out-of-line definition. The compiler uses the calling convention specified during declaration at the point of definition.
 
 ## See also
 
-[Argument Passing and Naming Conventions](../cpp/argument-passing-and-naming-conventions.md)
+[Argument passing and naming conventions](../cpp/argument-passing-and-naming-conventions.md)