[llvm] [AMDGPU][GlobalISel] Add RegBankLegalize support for G_READCYCLECOUNTER (PR #165754)

[via llvm-commits]

https://github.com/vangthao95 created https://github.com/llvm/llvm-project/pull/165754

None

>From 8d5f2e0881ac4041419ad28ce7a7f195b42a27e0 Mon Sep 17 00:00:00 2001
From: Vang Thao <vthao at amd.com>
Date: Thu, 30 Oct 2025 10:40:39 -0700
Subject: [PATCH] [AMDGPU][GlobalISel] Add RegBankLegalize support for
 G_READCYCLECOUNTER

---
 .../lib/Target/AMDGPU/AMDGPURegBankLegalizeRules.cpp |  2 ++
 llvm/test/CodeGen/AMDGPU/readcyclecounter.ll         | 12 ++++++------
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/llvm/lib/Target/AMDGPU/AMDGPURegBankLegalizeRules.cpp b/llvm/lib/Target/AMDGPU/AMDGPURegBankLegalizeRules.cpp
index 01abd358ff595..98b0971876a7c 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPURegBankLegalizeRules.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPURegBankLegalizeRules.cpp
@@ -915,6 +915,8 @@ RegBankLegalizeRules::RegBankLegalizeRules(const GCNSubtarget &_ST,
 
   addRulesForGOpcs({G_READSTEADYCOUNTER}, Standard).Uni(S64, {{Sgpr64}, {}});
 
+  addRulesForGOpcs({G_READCYCLECOUNTER}).Any({{UniS64}, {{Sgpr64}, {}}});
+
   bool hasSALUFloat = ST->hasSALUFloatInsts();
 
   addRulesForGOpcs({G_FADD}, Standard)
diff --git a/llvm/test/CodeGen/AMDGPU/readcyclecounter.ll b/llvm/test/CodeGen/AMDGPU/readcyclecounter.ll
index f67cbe381bfad..ddb522a82880b 100644
--- a/llvm/test/CodeGen/AMDGPU/readcyclecounter.ll
+++ b/llvm/test/CodeGen/AMDGPU/readcyclecounter.ll
@@ -1,17 +1,17 @@
 ; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=tahiti < %s | FileCheck -check-prefix=MEMTIME -check-prefix=SIVI -check-prefix=GCN %s
 ; -global-isel=1 SI run line skipped since store not yet implemented.
 ; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=tonga < %s | FileCheck -check-prefix=MEMTIME -check-prefix=SIVI -check-prefix=GCN %s
-; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=tonga < %s | FileCheck -check-prefix=MEMTIME -check-prefix=SIVI -check-prefix=GCN %s
+; RUN: llc -global-isel=1 -new-reg-bank-select -mtriple=amdgcn -mcpu=tonga < %s | FileCheck -check-prefix=MEMTIME -check-prefix=SIVI -check-prefix=GCN %s
 ; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1010 < %s | FileCheck -check-prefix=MEMTIME -check-prefix=GCN %s
-; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1010 < %s | FileCheck -check-prefix=MEMTIME -check-prefix=GCN %s
+; RUN: llc -global-isel=1 -new-reg-bank-select -mtriple=amdgcn -mcpu=gfx1010 < %s | FileCheck -check-prefix=MEMTIME -check-prefix=GCN %s
 ; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1030 < %s | FileCheck -check-prefixes=MEMTIME -check-prefix=GCN %s
-; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1030 < %s | FileCheck -check-prefixes=MEMTIME -check-prefix=GCN %s
+; RUN: llc -global-isel=1 -new-reg-bank-select -mtriple=amdgcn -mcpu=gfx1030 < %s | FileCheck -check-prefixes=MEMTIME -check-prefix=GCN %s
 ; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1100 -amdgpu-enable-vopd=0 < %s | FileCheck -check-prefixes=GETREG,GETREG-SDAG -check-prefix=GCN %s
-; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1100 -amdgpu-enable-vopd=0 < %s | FileCheck -check-prefixes=GETREG,GETREG-GISEL -check-prefix=GCN %s
+; RUN: llc -global-isel=1 -new-reg-bank-select -mtriple=amdgcn -mcpu=gfx1100 -amdgpu-enable-vopd=0 < %s | FileCheck -check-prefixes=GETREG,GETREG-GISEL -check-prefix=GCN %s
 ; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1200 < %s | FileCheck -check-prefixes=GCN,GFX12 %s
-; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1200 < %s | FileCheck -check-prefixes=GCN,GFX12 %s
+; RUN: llc -global-isel=1 -new-reg-bank-select -mtriple=amdgcn -mcpu=gfx1200 < %s | FileCheck -check-prefixes=GCN,GFX12 %s
 ; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1250 < %s | FileCheck -check-prefixes=GCN,GFX1250 %s
-; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1250 < %s | FileCheck -check-prefixes=GCN,GFX1250 %s
+; RUN: llc -global-isel=1 -new-reg-bank-select -mtriple=amdgcn -mcpu=gfx1250 < %s | FileCheck -check-prefixes=GCN,GFX1250 %s
 
 declare i64 @llvm.readcyclecounter() #0