Index: llvm/trunk/docs/LangRef.rst
===================================================================
--- llvm/trunk/docs/LangRef.rst
+++ llvm/trunk/docs/LangRef.rst
@@ -3654,8 +3654,8 @@
   ``d0-d31``, or ``q0-q15``.
 - ``x``: A 32, 64, or 128-bit floating-point/SIMD register: ``s0-s15``,
   ``d0-d7``, or ``q0-q3``.
-- ``t``: A floating-point/SIMD register, only supports 32-bit values:
-  ``s0-s31``.
+- ``t``: A low floating-point/SIMD register: ``s0-s31``, ``d0-d16``, or
+  ``q0-q8``.
 
 ARM's Thumb1 mode:
 
@@ -3674,8 +3674,8 @@
   ``d0-d31``, or ``q0-q15``.
 - ``x``: A 32, 64, or 128-bit floating-point/SIMD register: ``s0-s15``,
   ``d0-d7``, or ``q0-q3``.
-- ``t``: A floating-point/SIMD register, only supports 32-bit values:
-  ``s0-s31``.
+- ``t``: A low floating-point/SIMD register: ``s0-s31``, ``d0-d16``, or
+  ``q0-q8``.
 
 
 Hexagon:
Index: llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp
===================================================================
--- llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp
+++ llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp
@@ -13467,8 +13467,14 @@
         return RCPair(0U, &ARM::QPR_8RegClass);
       break;
     case 't':
+      if (VT == MVT::Other)
+        break;
       if (VT == MVT::f32 || VT == MVT::i32)
         return RCPair(0U, &ARM::SPRRegClass);
+      if (VT.getSizeInBits() == 64)
+        return RCPair(0U, &ARM::DPR_VFP2RegClass);
+      if (VT.getSizeInBits() == 128)
+        return RCPair(0U, &ARM::QPR_VFP2RegClass);
       break;
     }
   }
Index: llvm/trunk/test/CodeGen/ARM/inlineasm-error-t-toofewregs.ll
===================================================================
--- llvm/trunk/test/CodeGen/ARM/inlineasm-error-t-toofewregs.ll
+++ llvm/trunk/test/CodeGen/ARM/inlineasm-error-t-toofewregs.ll
@@ -0,0 +1,9 @@
+; RUN: not llc -mtriple=armv8-eabi -mattr=+neon %s -o /dev/null 2<&1 | FileCheck %s
+
+; CHECK: inline assembly requires more registers than available
+define <4 x float> @t-constraint-float-vectors-too-few-regs(<4 x float> %a, <4 x float> %b) {
+entry:
+	%0 = tail call { <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float> } asm "vadd.F32 $0, $9, $10\0A\09vadd.F32 $1, $9, $10\0A\09vadd.F32 $2, $9, $10\0A\09vadd.F32 $3, $9, $10\0A\09vadd.F32 $4, $9, $10\0A\09vadd.F32 $5, $9, $10\0A\09vadd.F32 $6, $9, $10\0A\09vadd.F32 $7, $9, $10\0A\09vadd.F32 $8, $9, $10", "=t,=t,=t,=t,=t,=t,=t,=t,=t,=t,t,t"(<4 x float> %a, <4 x float> %b)
+	%asmresult = extractvalue { <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float>, <4 x float> } %0, 0
+	ret <4 x float> %asmresult
+}
Index: llvm/trunk/test/CodeGen/ARM/inlineasm.ll
===================================================================
--- llvm/trunk/test/CodeGen/ARM/inlineasm.ll
+++ llvm/trunk/test/CodeGen/ARM/inlineasm.ll
@@ -16,3 +16,35 @@
 	%ret = call float asm "vcvt.f32.s32 $0, $1\0A", "=t,t"(i32 %i)
 	ret float %ret
 }
+
+define <2 x i32> @t-constraint-int-vector-64bit(<2 x float> %x) {
+entry:
+	; CHECK-LABEL: t-constraint-int-vector-64bit
+	; CHECK: vcvt.s32.f32 {{d[0-9]+}}, {{d[0-9]+}}
+  %0 = tail call <2 x i32> asm "vcvt.s32.f32 $0, $1", "=t,t"(<2 x float> %x)
+  ret <2 x i32> %0
+}
+
+define <4 x i32> @t-constraint-int-vector-128bit(<4 x float> %x) {
+entry:
+	; CHECK-LABEL: t-constraint-int-vector-128bit
+	; CHECK: vcvt.s32.f32 {{q[0-7]}}, {{q[0-7]}}
+  %0 = tail call <4 x i32> asm "vcvt.s32.f32 $0, $1", "=t,t"(<4 x float> %x)
+  ret <4 x i32> %0
+}
+
+define <2 x float> @t-constraint-float-vector-64bit(<2 x float> %a, <2 x float> %b) {
+entry:
+	; CHECK-LABEL: t-constraint-float-vector-64bit
+	; CHECK: vadd.f32 d{{[0-9]+}}, d{{[0-9]+}}, d{{[0-9]+}}
+	%0 = tail call <2 x float> asm "vadd.f32 $0, $1, $2", "=t,t,t"(<2 x float> %a, <2 x float> %b)
+	ret <2 x float> %0
+}
+
+define <4 x float> @t-constraint-float-vector-128bit(<4 x float> %a, <4 x float> %b) {
+entry:
+	; CHECK-LABEL: t-constraint-float-vector-128bit
+	; CHECK: vadd.f32 q{{[0-7]}}, q{{[0-7]}}, q{{[0-7]}}
+	%0 = tail call <4 x float> asm "vadd.f32 $0, $1, $2", "=t,t,t"(<4 x float> %a, <4 x float> %b)
+	ret <4 x float> %0
+}