[AMDGPU] Remove s_cmpk_* for GFX12 (llvm#75497)

No GFX12 encoding was added for these. This patch adds tests that they
are not recognized by the assembler and defends against generating them
in codegen.

Author: jayfoad

llvm/lib/Target/AMDGPU/GCNSubtarget.h

@@ -830,6 +830,9 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
 
   bool hasInstPrefetch() const { return getGeneration() >= GFX10; }
 
+  // Has s_cmpk_* instructions.
+  bool hasSCmpK() const { return getGeneration() < GFX12; }
+
   // Scratch is allocated in 256 dword per wave blocks for the entire
   // wavefront. When viewed from the perspective of an arbitrary workitem, this
   // is 4-byte aligned.

llvm/lib/Target/AMDGPU/SIShrinkInstructions.cpp

@@ -211,6 +211,9 @@ void SIShrinkInstructions::copyExtraImplicitOps(MachineInstr &NewMI,
 }
 
 void SIShrinkInstructions::shrinkScalarCompare(MachineInstr &MI) const {
+  if (!ST->hasSCmpK())
+    return;
+
   // cmpk instructions do scc = dst <cc op> imm16, so commute the instruction to
   // get constants on the RHS.
   if (!MI.getOperand(0).isReg())

llvm/test/MC/AMDGPU/gfx12_unsupported.s

@@ -43,6 +43,42 @@ ds_sub_gs_reg_rtn v[0:1], v2 gds
 ds_wrap_rtn_b32 v0, v1, v2, v3
 // CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
 
+s_cmpk_eq_i32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_lg_i32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_gt_i32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_ge_i32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_lt_i32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_le_i32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_eq_u32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_lg_u32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_gt_u32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_ge_u32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_lt_u32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
+s_cmpk_le_u32 s0, 0
+// CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU
+
 ds_gws_sema_release_all gds
 // CHECK: :[[@LINE-1]]:{{[0-9]+}}: error: instruction not supported on this GPU