[LangRef] *.overflow instrinsics now support vectors

[RKSimon]

Summary

We have all the necessary legalization, expansion and unrolling support required for the *.overflow intrinsics with vector types, so update the docs to make that clear.

Note: vectorization is not in place yet (the non-homogenous return types aren't well supported) so we still must explicitly use the vectors intrinsics and not reply on slp/loop.

[efriedma]

LGTM

llvm/trunk/docs/LangRef.rst

 
 '``llvm.sadd.with.overflow.*``' Intrinsics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Syntax:
 """""""
 
 This is an overloaded intrinsic. You can use ``llvm.sadd.with.overflow``
-on any integer bit width.
+on any integer bit width or vectors of integers.
 
 ::
 
       declare {i16, i1} @llvm.sadd.with.overflow.i16(i16 %a, i16 %b)
       declare {i32, i1} @llvm.sadd.with.overflow.i32(i32 %a, i32 %b)
       declare {i64, i1} @llvm.sadd.with.overflow.i64(i64 %a, i64 %b)
+      declare {<4 x i32>, <4 x i1>} @llvm.sadd.with.overflow.v4i32(<4 x i32> %a, <4 x i32> %b)
 
 Overview:
 """""""""
 
 The '``llvm.sadd.with.overflow``' family of intrinsic functions perform
 a signed addition of the two arguments, and indicate whether an overflow
 occurred during the signed summation.
 

 
 '``llvm.uadd.with.overflow.*``' Intrinsics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Syntax:
 """""""
 
 This is an overloaded intrinsic. You can use ``llvm.uadd.with.overflow``
-on any integer bit width.
+on any integer bit width or vectors of integers.
 
 ::
 
       declare {i16, i1} @llvm.uadd.with.overflow.i16(i16 %a, i16 %b)
       declare {i32, i1} @llvm.uadd.with.overflow.i32(i32 %a, i32 %b)
       declare {i64, i1} @llvm.uadd.with.overflow.i64(i64 %a, i64 %b)
+      declare {<4 x i32>, <4 x i1>} @llvm.uadd.with.overflow.v4i32(<4 x i32> %a, <4 x i32> %b)
 
 Overview:
 """""""""
 
 The '``llvm.uadd.with.overflow``' family of intrinsic functions perform
 an unsigned addition of the two arguments, and indicate whether a carry
 occurred during the unsigned summation.
 

 
 '``llvm.ssub.with.overflow.*``' Intrinsics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Syntax:
 """""""
 
 This is an overloaded intrinsic. You can use ``llvm.ssub.with.overflow``
-on any integer bit width.
+on any integer bit width or vectors of integers.
 
 ::
 
       declare {i16, i1} @llvm.ssub.with.overflow.i16(i16 %a, i16 %b)
       declare {i32, i1} @llvm.ssub.with.overflow.i32(i32 %a, i32 %b)
       declare {i64, i1} @llvm.ssub.with.overflow.i64(i64 %a, i64 %b)
+      declare {<4 x i32>, <4 x i1>} @llvm.ssub.with.overflow.v4i32(<4 x i32> %a, <4 x i32> %b)
 
 Overview:
 """""""""
 
 The '``llvm.ssub.with.overflow``' family of intrinsic functions perform
 a signed subtraction of the two arguments, and indicate whether an
 overflow occurred during the signed subtraction.
 

 
 '``llvm.usub.with.overflow.*``' Intrinsics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Syntax:
 """""""
 
 This is an overloaded intrinsic. You can use ``llvm.usub.with.overflow``
-on any integer bit width.
+on any integer bit width or vectors of integers.
 
 ::
 
       declare {i16, i1} @llvm.usub.with.overflow.i16(i16 %a, i16 %b)
       declare {i32, i1} @llvm.usub.with.overflow.i32(i32 %a, i32 %b)
       declare {i64, i1} @llvm.usub.with.overflow.i64(i64 %a, i64 %b)
+      declare {<4 x i32>, <4 x i1>} @llvm.usub.with.overflow.v4i32(<4 x i32> %a, <4 x i32> %b)
 
 Overview:
 """""""""
 
 The '``llvm.usub.with.overflow``' family of intrinsic functions perform
 an unsigned subtraction of the two arguments, and indicate whether an
 overflow occurred during the unsigned subtraction.
 

 
 '``llvm.smul.with.overflow.*``' Intrinsics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Syntax:
 """""""
 
 This is an overloaded intrinsic. You can use ``llvm.smul.with.overflow``
-on any integer bit width.
+on any integer bit width or vectors of integers.
 
 ::
 
       declare {i16, i1} @llvm.smul.with.overflow.i16(i16 %a, i16 %b)
       declare {i32, i1} @llvm.smul.with.overflow.i32(i32 %a, i32 %b)
       declare {i64, i1} @llvm.smul.with.overflow.i64(i64 %a, i64 %b)
+      declare {<4 x i32>, <4 x i1>} @llvm.smul.with.overflow.v4i32(<4 x i32> %a, <4 x i32> %b)
 
 Overview:
 """""""""
 
 The '``llvm.smul.with.overflow``' family of intrinsic functions perform
 a signed multiplication of the two arguments, and indicate whether an
 overflow occurred during the signed multiplication.
 

 
 '``llvm.umul.with.overflow.*``' Intrinsics
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Syntax:
 """""""
 
 This is an overloaded intrinsic. You can use ``llvm.umul.with.overflow``
-on any integer bit width.
+on any integer bit width or vectors of integers.
 
 ::
 
       declare {i16, i1} @llvm.umul.with.overflow.i16(i16 %a, i16 %b)
       declare {i32, i1} @llvm.umul.with.overflow.i32(i32 %a, i32 %b)
       declare {i64, i1} @llvm.umul.with.overflow.i64(i64 %a, i64 %b)
+      declare {<4 x i32>, <4 x i1>} @llvm.umul.with.overflow.v4i32(<4 x i32> %a, <4 x i32> %b)
 
 Overview:
 """""""""
 
 The '``llvm.umul.with.overflow``' family of intrinsic functions perform
 a unsigned multiplication of the two arguments, and indicate whether an
 overflow occurred during the unsigned multiplication.