[llvm] [AArch64][GISel] Support SVE with 128-bit min-size for G_LOAD and G_STORE (PR #92130)

[David Green via llvm-commits]

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@@ -0,0 +1,50 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=aarch64-linux-gnu -mattr=+sve -global-isel -aarch64-enable-sve-gisel=true < %s | FileCheck %s
+
+define void @scalable_v16i8(ptr %l0, ptr %l1) {
+; CHECK-LABEL: scalable_v16i8:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    ptrue p0.b
+; CHECK-NEXT:    ld1b { z0.b }, p0/z, [x0]
+; CHECK-NEXT:    st1b { z0.b }, p0, [x1]
+; CHECK-NEXT:    ret
+  %l3 = load <vscale x 16 x i8>, ptr %l0, align 16
+  store <vscale x 16 x i8> %l3, ptr %l1, align 16
+  ret void
+}
+
+define void @scalable_v8i16(ptr %l0, ptr %l1) {
+; CHECK-LABEL: scalable_v8i16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    ptrue p0.h
+; CHECK-NEXT:    ld1h { z0.h }, p0/z, [x0]
+; CHECK-NEXT:    st1h { z0.h }, p0, [x1]
+; CHECK-NEXT:    ret
+  %l3 = load <vscale x 8 x i16>, ptr %l0, align 16
+  store <vscale x 8 x i16> %l3, ptr %l1, align 16
+  ret void
+}
+
+define void @scalable_v4i32(ptr %l0, ptr %l1) {
+; CHECK-LABEL: scalable_v4i32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    ptrue p0.s
+; CHECK-NEXT:    ld1w { z0.s }, p0/z, [x0]
+; CHECK-NEXT:    st1w { z0.s }, p0, [x1]
+; CHECK-NEXT:    ret
+  %l3 = load <vscale x 4 x i32>, ptr %l0, align 16
+  store <vscale x 4 x i32> %l3, ptr %l1, align 16
+  ret void
+}
+
+define void @scalable_v2i64(ptr %l0, ptr %l1) {
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davemgreen wrote:

There are two options for ptrs that are stored
- Scalars are copied it to integer in AArch64InstructionSelector::preISelLower
- Vectors are bitcast to integer vectors in AArch64LegalizerInfo::legalizeLoadStore, by marking them as custom.
We only really need one method though. The vector stores should be using bitcastIf not customIf and the scalars could hopefully use the same method. This might mean that G_BITCAST needed to be supported for scalable vectors though, if it was using the same method.

https://github.com/llvm/llvm-project/pull/92130