[llvm] [PowerPC] Add Dense Math binary integer outer-Product accumulate to DMR Instructions (PR #130791)

[Maryam Moghadas via llvm-commits]

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@@ -1701,6 +1708,20 @@ let TargetPrefix = "ppc" in {
                             [llvm_v512i1_ty, llvm_v16i8_ty, llvm_v16i8_ty,
                              llvm_i32_ty, llvm_i32_ty, llvm_i32_ty],
                             [IntrNoMem]>;
+  defm int_ppc_mma_dmxvi8gerx4 :
+       PowerPC_MMA_DMR_PP_Intrinsic<[llvm_v256i1_ty, llvm_v16i8_ty]>;
+  defm int_ppc_mma_pmdmxvi8gerx4 :
+       PowerPC_MMA_DMR_PP_Intrinsic<[llvm_v256i1_ty, llvm_v16i8_ty, llvm_i32_ty,
+                                     llvm_i32_ty, llvm_i32_ty]>;
----------------
maryammo wrote:

when I add the ImmArg to the intrinsics definition, the original types that make sure the mask values are fitted into 2/4/8 bits wont work. 

def Msk2Imm : ImmLeaf<i32, [{ return isUInt<2>(Imm); }]>; -
def Msk4Imm : ImmLeaf<i32, [{ return isUInt<4>(Imm); }]>;
def Msk8Imm : ImmLeaf<i32, [{ return isUInt<8>(Imm); }]>;

and an IR test like the following

d```
eclare <1024 x i1> @llvm.ppc.mma.pmdmxvi8gerx4spp(<1024 x i1>, <256 x i1>, <16 x i8>, i32 immarg, i32 immarg, i32 immarg)

define dso_local void @test_pmdmxvi8gerx4spp(ptr %vop, ptr %vpp, ptr %vcp, ptr %resp) {
entry:
  %0 = load <1024 x i1>, ptr %vop, align 64
  %1 = load <256 x i1>, ptr %vpp, align 32
  %2 = load <16 x i8>, ptr %vcp, align 32
  %3 = tail call <1024 x i1> @llvm.ppc.mma.pmdmxvi8gerx4spp(<1024 x i1> %0, <256 x i1> %1, <16 x i8> %2, i32 0, i32 0, i32 0)
  store <1024 x i1> %3, ptr %resp, align 64
  ret void
}
```

fails with 
`LLVM ERROR: Cannot select: intrinsic %llvm.ppc.mma.pmdmxvi8gerx4pp
`

By changing the Pat for them to use i32 instead of Msk*Imm, the IR compiles fine, however it wont have the original constraint on the masks.  


https://github.com/llvm/llvm-project/pull/130791