[DPWBS-1211] Adding legalization and test case for G_VASTART.

llvm/lib/Target/TriCore/TriCoreLegalizerInfo.cpp

@@ -422,6 +422,11 @@ TriCoreLegalizerInfo::TriCoreLegalizerInfo(const TriCoreSubtarget &ST) {
   // G_BRINDIRECT is valid for p0 types.
   getActionDefinitionsBuilder(G_BRINDIRECT).legalFor({p0});
 
+  // Variadic Arguments
+
+  // G_VASTART is legal for pointer type
+  getActionDefinitionsBuilder(G_VASTART).legalFor({p0});
+
   computeTables();
   verify(*ST.getInstrInfo());
 }

llvm/test/CodeGen/TriCore/GlobalIsel/legalize-vastart.mir

@@ -0,0 +1,33 @@
+# RUN: llc -O0 -mtriple=tricore -global-isel -run-pass=legalizer \
+# RUN:   -verify-machineinstrs %s -o - | FileCheck %s
+
+--- |
+  define dso_local void @vastart_test(i32 %n, ...) {
+  entry:
+    %vl = alloca i8*, align 4
+    %vl1 = bitcast i8** %vl to i8*
+    call void @llvm.va_start(i8* %vl1)
+    ret void
+  }
+
+  declare void @llvm.va_start(i8*)
+...
+---
+name:            vastart_test
+legalized:       false
+stack:
+  - { id: 0, name: vl, type: default, offset: 0, size: 4, alignment: 4 }
+body:             |
+  bb.0:
+    liveins: $d4
+
+    ; CHECK-LABEL: name: vastart_test
+    ; CHECK: [[COPY:%[0-9]+]]:_(s32) = COPY $d4
+    ; CHECK: [[FI:%[0-9]+]]:_(p0) = G_FRAME_INDEX %stack.0.vl
+    ; CHECK: G_VASTART [[FI]](p0) :: (store 4 into %ir.vl1, align 1)
+    ; CHECK: RET implicit $a11
+    %0:_(s32) = COPY $d4
+    %1:_(p0) = G_FRAME_INDEX %stack.0.vl
+    G_VASTART %1(p0) :: (store 4 into %ir.vl1, align 1)
+    RET implicit $a11
+...