[llvm] [Utils][update_mc_test_checks] Support updating round-trip tests. (PR #164425)

[Ivan Kosarev via llvm-commits]

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@@ -5,7 +5,8 @@
 // RUN: not llvm-mc -triple=amdgcn -mcpu=gfx900 -show-encoding %s | FileCheck %s --check-prefixes=GFX8PLUS,GFX89,GFX9
 // RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1100 -show-encoding %s | FileCheck %s --check-prefixes=GFX8PLUS,GFX11
 // RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1200 -show-encoding %s | FileCheck %s --check-prefixes=GFX8PLUS,GFX12XX,GFX12
-// RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1250 -mattr=+real-true16 -show-encoding %s | FileCheck %s --check-prefixes=GFX8PLUS,GFX12XX,GFX1250
+// RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1250 -mattr=+real-true16 -show-encoding %s | FileCheck %s --check-prefixes=GFX8PLUS,GFX12XX,GFX1250,GFX1250-ASM
+// RUN: not llvm-mc -triple=amdgcn -mcpu=gfx1250 -mattr=+real-true16 -show-encoding %s | %extract-encodings | llvm-mc -triple=amdgcn -mcpu=gfx1250 -mattr=+real-true16 -disassemble -show-encoding | FileCheck %s --check-prefixes=GFX8PLUS,GFX12XX,GFX1250,GFX1250-DIS
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kosarev wrote:

A lit substitution added in https://github.com/llvm/llvm-project/pull/92895/files#diff-772a3091d3b29185028fd2ab6ac34b3d49dcce27080f12787179ef8f99a27c26 to extract instruction codes, to be used in combined asm/disasm tests.

https://github.com/llvm/llvm-project/pull/164425