[GlobalIsel] Import vscale (#88240)

#84542

Author: Thorsten Schütt

llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp

@@ -2550,6 +2550,10 @@ bool IRTranslator::translateKnownIntrinsic(const CallInst &CI, Intrinsic::ID ID,
     MIRBuilder.buildInstr(TargetOpcode::G_RESET_FPMODE, {}, {});
     return true;
   }
+  case Intrinsic::vscale: {
+    MIRBuilder.buildVScale(getOrCreateVReg(CI), 1);
+    return true;
+  }
   case Intrinsic::prefetch: {
     Value *Addr = CI.getOperand(0);
     unsigned RW = cast<ConstantInt>(CI.getOperand(1))->getZExtValue();

llvm/test/CodeGen/AArch64/GlobalISel/irtranslator-vscale.ll

@@ -0,0 +1,52 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+; RUN: llc -O0 -mtriple=aarch64-linux-gnu -global-isel -stop-after=irtranslator %s -o - | FileCheck %s
+
+define i64 @call_vscale_i64() {
+  ; CHECK-LABEL: name: call_vscale_i64
+  ; CHECK: bb.1.entry:
+  ; CHECK-NEXT:   [[VSCALE:%[0-9]+]]:_(s64) = G_VSCALE i64 1
+  ; CHECK-NEXT:   $x0 = COPY [[VSCALE]](s64)
+  ; CHECK-NEXT:   RET_ReallyLR implicit $x0
+entry:
+  %vscale = call i64 @llvm.vscale.64()
+  ret i64 %vscale
+}
+
+define i64 @call_vscale_i32() {
+  ; CHECK-LABEL: name: call_vscale_i32
+  ; CHECK: bb.1.entry:
+  ; CHECK-NEXT:   [[VSCALE:%[0-9]+]]:_(s32) = G_VSCALE i32 1
+  ; CHECK-NEXT:   [[ZEXT:%[0-9]+]]:_(s64) = G_ZEXT [[VSCALE]](s32)
+  ; CHECK-NEXT:   $x0 = COPY [[ZEXT]](s64)
+  ; CHECK-NEXT:   RET_ReallyLR implicit $x0
+entry:
+  %vscale = call i32 @llvm.vscale.32()
+  %zext = zext i32 %vscale to i64
+  ret i64 %zext
+}
+
+define i64 @call_vscale_i16() {
+  ; CHECK-LABEL: name: call_vscale_i16
+  ; CHECK: bb.1.entry:
+  ; CHECK-NEXT:   [[VSCALE:%[0-9]+]]:_(s16) = G_VSCALE i16 1
+  ; CHECK-NEXT:   [[ZEXT:%[0-9]+]]:_(s64) = G_ZEXT [[VSCALE]](s16)
+  ; CHECK-NEXT:   $x0 = COPY [[ZEXT]](s64)
+  ; CHECK-NEXT:   RET_ReallyLR implicit $x0
+entry:
+  %vscale = call i16 @llvm.vscale.16()
+  %zext = zext i16 %vscale to i64
+  ret i64 %zext
+}
+
+define i64 @call_vscale_i8() {
+  ; CHECK-LABEL: name: call_vscale_i8
+  ; CHECK: bb.1.entry:
+  ; CHECK-NEXT:   [[VSCALE:%[0-9]+]]:_(s8) = G_VSCALE i8 1
+  ; CHECK-NEXT:   [[ZEXT:%[0-9]+]]:_(s64) = G_ZEXT [[VSCALE]](s8)
+  ; CHECK-NEXT:   $x0 = COPY [[ZEXT]](s64)
+  ; CHECK-NEXT:   RET_ReallyLR implicit $x0
+entry:
+  %vscale = call i8 @llvm.vscale.8()
+  %zext = zext i8 %vscale to i64
+  ret i64 %zext
+}