Index: llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp
===================================================================
--- llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -7972,7 +7972,7 @@
     Info.opc = ISD::INTRINSIC_VOID;
     // Conservatively set memVT to the entire set of vectors stored.
     unsigned NumElts = 0;
-    for (unsigned ArgI = 1, ArgE = I.getNumArgOperands(); ArgI < ArgE; ++ArgI) {
+    for (unsigned ArgI = 0, ArgE = I.getNumArgOperands(); ArgI < ArgE; ++ArgI) {
       Type *ArgTy = I.getArgOperand(ArgI)->getType();
       if (!ArgTy->isVectorTy())
         break;
Index: llvm/trunk/test/CodeGen/AArch64/multi-vector-store-size.ll
===================================================================
--- llvm/trunk/test/CodeGen/AArch64/multi-vector-store-size.ll
+++ llvm/trunk/test/CodeGen/AArch64/multi-vector-store-size.ll
@@ -0,0 +1,164 @@
+; RUN: llc -mtriple=aarch64-linux-gnu -stop-after=isel < %s | FileCheck %s
+
+declare void @llvm.aarch64.neon.st2.v4f32.p0f32(<4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st3.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st4.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, <4 x float>, float*)
+
+declare void @llvm.aarch64.neon.st1x2.v4f32.p0f32(<4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st1x3.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st1x4.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, <4 x float>, float*)
+
+declare void @llvm.aarch64.neon.st2lane.v4f32.p0f32(<4 x float>, <4 x float>, i64, float*)
+declare void @llvm.aarch64.neon.st3lane.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, i64, float*)
+declare void @llvm.aarch64.neon.st4lane.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, <4 x float>, i64, float*)
+
+define void @addstx(float* %res, <4 x float>* %a,  <4 x float>* %b, <4 x float>* %c, <4 x float>* %d) {
+  %al = load <4 x float>, <4 x float>* %a
+  %bl = load <4 x float>, <4 x float>* %b
+  %cl = load <4 x float>, <4 x float>* %c
+  %dl = load <4 x float>, <4 x float>* %d
+
+  %ar = fadd <4 x float> %al, %bl
+  %br = fadd <4 x float> %bl, %cl
+  %cr = fadd <4 x float> %cl, %dl
+  %dr = fadd <4 x float> %dl, %al
+
+; The sizes below are conservative.  AArch64TargetLowering
+; conservatively assumes the entire vector is stored.
+  tail call void @llvm.aarch64.neon.st2.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, float* %res)
+; CHECK: ST2Twov4s {{.*}} :: (store 32 {{.*}})
+  tail call void @llvm.aarch64.neon.st3.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, float* %res)
+; CHECK: ST3Threev4s {{.*}} :: (store 48 {{.*}})
+  tail call void @llvm.aarch64.neon.st4.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, <4 x float> %dr, float* %res)
+; CHECK: ST4Fourv4s {{.*}} :: (store 64 {{.*}})
+
+  ret void
+}
+
+define void @addst1x(float* %res, <4 x float>* %a,  <4 x float>* %b, <4 x float>* %c, <4 x float>* %d) {
+  %al = load <4 x float>, <4 x float>* %a
+  %bl = load <4 x float>, <4 x float>* %b
+  %cl = load <4 x float>, <4 x float>* %c
+  %dl = load <4 x float>, <4 x float>* %d
+
+  %ar = fadd <4 x float> %al, %bl
+  %br = fadd <4 x float> %bl, %cl
+  %cr = fadd <4 x float> %cl, %dl
+  %dr = fadd <4 x float> %dl, %al
+
+; The sizes below are conservative.  AArch64TargetLowering
+; conservatively assumes the entire vector is stored.
+  tail call void @llvm.aarch64.neon.st1x2.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, float* %res)
+; CHECK: ST1Twov4s {{.*}} :: (store 32 {{.*}})
+  tail call void @llvm.aarch64.neon.st1x3.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, float* %res)
+; CHECK: ST1Threev4s {{.*}} :: (store 48 {{.*}})
+  tail call void @llvm.aarch64.neon.st1x4.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, <4 x float> %dr, float* %res)
+; CHECK: ST1Fourv4s {{.*}} :: (store 64 {{.*}})
+
+  ret void
+}
+
+define void @addstxlane(float* %res, <4 x float>* %a,  <4 x float>* %b, <4 x float>* %c, <4 x float>* %d) {
+  %al = load <4 x float>, <4 x float>* %a
+  %bl = load <4 x float>, <4 x float>* %b
+  %cl = load <4 x float>, <4 x float>* %c
+  %dl = load <4 x float>, <4 x float>* %d
+
+  %ar = fadd <4 x float> %al, %bl
+  %br = fadd <4 x float> %bl, %cl
+  %cr = fadd <4 x float> %cl, %dl
+  %dr = fadd <4 x float> %dl, %al
+
+; The sizes below are conservative.  AArch64TargetLowering
+; conservatively assumes the entire vector is stored.
+  tail call void @llvm.aarch64.neon.st2lane.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, i64 1, float* %res)
+; CHECK: ST2i32 {{.*}} :: (store 32 {{.*}})
+  tail call void @llvm.aarch64.neon.st3lane.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, i64 1, float* %res)
+; CHECK: ST3i32 {{.*}} :: (store 48 {{.*}})
+  tail call void @llvm.aarch64.neon.st4lane.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, <4 x float> %dr, i64 1, float* %res)
+; CHECK: ST4i32 {{.*}} :: (store 64 {{.*}})
+
+  ret void
+}
+; RUN: llc -mtriple=aarch64-linux-gnu -stop-after=isel < %s | FileCheck %s
+
+declare void @llvm.aarch64.neon.st2.v4f32.p0f32(<4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st3.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st4.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, <4 x float>, float*)
+
+declare void @llvm.aarch64.neon.st1x2.v4f32.p0f32(<4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st1x3.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, float*)
+declare void @llvm.aarch64.neon.st1x4.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, <4 x float>, float*)
+
+declare void @llvm.aarch64.neon.st2lane.v4f32.p0f32(<4 x float>, <4 x float>, i64, float*)
+declare void @llvm.aarch64.neon.st3lane.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, i64, float*)
+declare void @llvm.aarch64.neon.st4lane.v4f32.p0f32(<4 x float>, <4 x float>, <4 x float>, <4 x float>, i64, float*)
+
+define void @addstx(float* %res, <4 x float>* %a,  <4 x float>* %b, <4 x float>* %c, <4 x float>* %d) {
+  %al = load <4 x float>, <4 x float>* %a
+  %bl = load <4 x float>, <4 x float>* %b
+  %cl = load <4 x float>, <4 x float>* %c
+  %dl = load <4 x float>, <4 x float>* %d
+
+  %ar = fadd <4 x float> %al, %bl
+  %br = fadd <4 x float> %bl, %cl
+  %cr = fadd <4 x float> %cl, %dl
+  %dr = fadd <4 x float> %dl, %al
+
+; The sizes below are conservative.  AArch64TargetLowering
+; conservatively assumes the entiew vector is stored.
+  tail call void @llvm.aarch64.neon.st2.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, float* %res)
+; CHECK: ST2Twov4s {{.*}} :: (store 32 {{.*}})
+  tail call void @llvm.aarch64.neon.st3.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, float* %res)
+; CHECK: ST3Threev4s {{.*}} :: (store 48 {{.*}})
+  tail call void @llvm.aarch64.neon.st4.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, <4 x float> %dr, float* %res)
+; CHECK: ST4Fourv4s {{.*}} :: (store 64 {{.*}})
+
+  ret void
+}
+
+define void @addst1x(float* %res, <4 x float>* %a,  <4 x float>* %b, <4 x float>* %c, <4 x float>* %d) {
+  %al = load <4 x float>, <4 x float>* %a
+  %bl = load <4 x float>, <4 x float>* %b
+  %cl = load <4 x float>, <4 x float>* %c
+  %dl = load <4 x float>, <4 x float>* %d
+
+  %ar = fadd <4 x float> %al, %bl
+  %br = fadd <4 x float> %bl, %cl
+  %cr = fadd <4 x float> %cl, %dl
+  %dr = fadd <4 x float> %dl, %al
+
+; The sizes below are conservative.  AArch64TargetLowering
+; conservatively assumes the entiew vector is stored.
+  tail call void @llvm.aarch64.neon.st1x2.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, float* %res)
+; CHECK: ST1Twov4s {{.*}} :: (store 32 {{.*}})
+  tail call void @llvm.aarch64.neon.st1x3.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, float* %res)
+; CHECK: ST1Threev4s {{.*}} :: (store 48 {{.*}})
+  tail call void @llvm.aarch64.neon.st1x4.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, <4 x float> %dr, float* %res)
+; CHECK: ST1Fourv4s {{.*}} :: (store 64 {{.*}})
+
+  ret void
+}
+
+define void @addstxlane(float* %res, <4 x float>* %a,  <4 x float>* %b, <4 x float>* %c, <4 x float>* %d) {
+  %al = load <4 x float>, <4 x float>* %a
+  %bl = load <4 x float>, <4 x float>* %b
+  %cl = load <4 x float>, <4 x float>* %c
+  %dl = load <4 x float>, <4 x float>* %d
+
+  %ar = fadd <4 x float> %al, %bl
+  %br = fadd <4 x float> %bl, %cl
+  %cr = fadd <4 x float> %cl, %dl
+  %dr = fadd <4 x float> %dl, %al
+
+; The sizes below are conservative.  AArch64TargetLowering
+; conservatively assumes the entiew vector is stored.
+  tail call void @llvm.aarch64.neon.st2lane.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, i64 1, float* %res)
+; CHECK: ST2i32 {{.*}} :: (store 32 {{.*}})
+  tail call void @llvm.aarch64.neon.st3lane.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, i64 1, float* %res)
+; CHECK: ST3i32 {{.*}} :: (store 48 {{.*}})
+  tail call void @llvm.aarch64.neon.st4lane.v4f32.p0f32(<4 x float> %ar, <4 x float> %br, <4 x float> %cr, <4 x float> %dr, i64 1, float* %res)
+; CHECK: ST4i32 {{.*}} :: (store 64 {{.*}})
+
+  ret void
+}