[llvm] [PowerPC] Add DMR and WACC COPY support (PR #149129)

[Lei Huang via llvm-commits]

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@@ -0,0 +1,245 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -verify-machineinstrs -mtriple=powerpc64le-unknown-linux-gnu \
+; RUN:   -mcpu=future -ppc-asm-full-reg-names \
+; RUN:   -ppc-vsr-nums-as-vr < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -mtriple=powerpc64-ibm-aix \
+; RUN:   -mcpu=future -ppc-asm-full-reg-names \
+; RUN:   -ppc-vsr-nums-as-vr < %s | FileCheck %s --check-prefix=CHECK-BE
+
+define void @test_wacc_copy(ptr noundef %vdmrp, ptr noundef %vpp, <16 x i8> noundef %vc, ptr noundef %resp) #0 {
+; CHECK-LABEL: test_wacc_copy:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    std r31, -8(r1)
+; CHECK-NEXT:    std r30, -16(r1)
+; CHECK-NEXT:    mr r30, r1
+; CHECK-NEXT:    clrldi r0, r1, 57
+; CHECK-NEXT:    subfic r0, r0, -384
+; CHECK-NEXT:    stdux r1, r1, r0
+; CHECK-NEXT:    .cfi_def_cfa_register r30
+; CHECK-NEXT:    .cfi_offset r31, -8
+; CHECK-NEXT:    .cfi_offset r30, -16
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lei137 wrote:

Is the attribute `#0` needed to reproduce the test?
adding `nounwind` to the function will eliminate these 

https://github.com/llvm/llvm-project/pull/149129