[llvm] [AMDGPU] Add GFX12 S_ALLOC_VGPR instruction (PR #130018)

[Matt Arsenault via llvm-commits]

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@@ -1,5 +1,14 @@
 # RUN: llvm-mc -triple=amdgcn -mcpu=gfx1200 -disassemble -show-encoding < %s | FileCheck -check-prefixes=GFX12 %s
 
+# GFX12: s_alloc_vgpr 0x1235                          ; encoding: [0xff,0x53,0x80,0xbe,0x35,0x12,0x00,0x00]
+0xff,0x53,0x80,0xbe,0x35,0x12,0x00,0x00
+
+# GFX12: s_alloc_vgpr 18                              ; encoding: [0x92,0x53,0x80,0xbe]
+0x92,0x53,0x80,0xbe
+
+# GFX12: s_alloc_vgpr s35                             ; encoding: [0x23,0x53,0x80,0xbe]
+0x23,0x53,0x80,0xbe
+
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arsenm wrote:

Does this need error tests for VGPRs, or the exotic scalar registers? 

https://github.com/llvm/llvm-project/pull/130018