From de59ec81550148e0f0205ceeb76c25c1f79e9f75 Mon Sep 17 00:00:00 2001
From: Stanislav Mekhanoshin <Stanislav.Mekhanoshin@amd.com>
Date: Wed, 3 Dec 2025 12:09:20 -0800
Subject: [PATCH] [AMDGPU] Add verifier for flat_scr_base_hi read hazard

---
 llvm/lib/Target/AMDGPU/SIInstrInfo.cpp        | 11 ++++
 .../AMDGPU/hazard-gfx1250-flat-src-hi.mir     | 66 +++++++++++++++++++
 2 files changed, 77 insertions(+)
 create mode 100644 llvm/test/MachineVerifier/AMDGPU/hazard-gfx1250-flat-src-hi.mir

diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
index 7535407741f1f..6d2110957002a 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -5808,6 +5808,17 @@ bool SIInstrInfo::verifyInstruction(const MachineInstr &MI,
     }
   }
 
+  if (ST.hasFlatScratchHiInB64InstHazard() && isSALU(MI) &&
+      MI.readsRegister(AMDGPU::SRC_FLAT_SCRATCH_BASE_HI, nullptr)) {
+    const MachineOperand *Dst = getNamedOperand(MI, AMDGPU::OpName::sdst);
+    if ((Dst && RI.getRegClassForReg(MRI, Dst->getReg()) ==
+                    &AMDGPU::SReg_64RegClass) ||
+        Opcode == AMDGPU::S_BITCMP0_B64 || Opcode == AMDGPU::S_BITCMP1_B64) {
+      ErrInfo = "Instruction cannot read flat_scratch_base_hi";
+      return false;
+    }
+  }
+
   return true;
 }
 
diff --git a/llvm/test/MachineVerifier/AMDGPU/hazard-gfx1250-flat-src-hi.mir b/llvm/test/MachineVerifier/AMDGPU/hazard-gfx1250-flat-src-hi.mir
new file mode 100644
index 0000000000000..0b48bad23db62
--- /dev/null
+++ b/llvm/test/MachineVerifier/AMDGPU/hazard-gfx1250-flat-src-hi.mir
@@ -0,0 +1,66 @@
+# RUN: not --crash llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1250 -run-pass=none -filetype=null %s 2>&1 | FileCheck %s
+
+---
+name:            salu_64_bit_inst_reads_flat_scratch_base_hi
+tracksRegLiveness: true
+body:             |
+  bb.0:
+
+    %0:sreg_64 = IMPLICIT_DEF
+    $sgpr0_sgpr1 = IMPLICIT_DEF
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_ASHR_I64
+
+    %1:sreg_64 = S_ASHR_I64 %0:sreg_64, $src_flat_scratch_base_hi, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_LSHL_B64
+
+    %2:sreg_64 = S_LSHL_B64 %0:sreg_64, $src_flat_scratch_base_hi, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_LSHR_B64
+
+    %3:sreg_64 = S_LSHR_B64 %0:sreg_64, $src_flat_scratch_base_hi, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BFE_I64
+
+    %4:sreg_64 = S_BFE_I64 %0:sreg_64, $src_flat_scratch_base_hi, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BFE_U64
+
+    %5:sreg_64 = S_BFE_U64 %0:sreg_64, $src_flat_scratch_base_hi, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BFM_B64
+
+    %6:sreg_64 = S_BFM_B64 $src_flat_scratch_base_hi, 1, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BITCMP0_B64
+
+    S_BITCMP0_B64 %0:sreg_64, $src_flat_scratch_base_hi, implicit $scc, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BITCMP1_B64
+
+    S_BITCMP1_B64 %0:sreg_64, $src_flat_scratch_base_hi, implicit $scc, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BITREPLICATE_B64_B32
+
+    %7:sreg_64 = S_BITREPLICATE_B64_B32 $src_flat_scratch_base_hi, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BITSET0_B64
+
+    $sgpr0_sgpr1 = S_BITSET0_B64 $src_flat_scratch_base_hi, $sgpr0_sgpr1, implicit-def $scc
+
+    ; CHECK: *** Bad machine code: Instruction cannot read flat_scratch_base_hi ***
+    ; CHECK: S_BITSET1_B64
+
+    $sgpr0_sgpr1 = S_BITSET1_B64 $src_flat_scratch_base_hi, $sgpr0_sgpr1, implicit-def $scc
+...