[VP][RISCV] Introduce llvm.vp.minimum/maximum intrinsics (#74840)

Although there are predicated versions of minnum/maxnum, the ones for
minimum/maximum are currently missing. This patch introduces these
intrinsics and implements their lowering to RISC-V.

1 files changed, 100 insertions, 0 deletions

diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index bc9cfb5..d58375c 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -20394,6 +20394,106 @@ Examples:
       %also.r = select <4 x i1> %mask, <4 x float> %t, <4 x float> poison
 
 
+.. _int_vp_minimum:
+
+'``llvm.vp.minimum.*``' Intrinsics
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+This is an overloaded intrinsic.
+
+::
+
+      declare <16 x float>  @llvm.vp.minimum.v16f32 (<16 x float> <left_op>, <16 x float> <right_op>, <16 x i1> <mask>, i32 <vector_length>)
+      declare <vscale x 4 x float>  @llvm.vp.minimum.nxv4f32 (<vscale x 4 x float> <left_op>, <vscale x 4 x float> <right_op>, <vscale x 4 x i1> <mask>, i32 <vector_length>)
+      declare <256 x double>  @llvm.vp.minimum.v256f64 (<256 x double> <left_op>, <256 x double> <right_op>, <256 x i1> <mask>, i32 <vector_length>)
+
+Overview:
+"""""""""
+
+Predicated floating-point minimum of two vectors of floating-point values,
+propagating NaNs and treating -0.0 as less than +0.0.
+
+Arguments:
+""""""""""
+
+The first two operands and the result have the same vector of floating-point type. The
+third operand is the vector mask and has the same number of elements as the
+result vector type. The fourth operand is the explicit vector length of the
+operation.
+
+Semantics:
+""""""""""
+
+The '``llvm.vp.minimum``' intrinsic performs floating-point minimum (:ref:`minimum <i_minimum>`)
+of the first and second vector operand on each enabled lane, the result being 
+NaN if either operand is a NaN. -0.0 is considered to be less than +0.0 for this
+intrinsic. The result on disabled lanes is a :ref:`poison value <poisonvalues>`. 
+The operation is performed in the default floating-point environment.
+
+Examples:
+"""""""""
+
+.. code-block:: llvm
+
+      %r = call <4 x float> @llvm.vp.minimum.v4f32(<4 x float> %a, <4 x float> %b, <4 x i1> %mask, i32 %evl)
+      ;; For all lanes below %evl, %r is lane-wise equivalent to %also.r
+
+      %t = call <4 x float> @llvm.minimum.v4f32(<4 x float> %a, <4 x float> %b)
+      %also.r = select <4 x i1> %mask, <4 x float> %t, <4 x float> poison
+
+
+.. _int_vp_maximum:
+
+'``llvm.vp.maximum.*``' Intrinsics
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+This is an overloaded intrinsic.
+
+::
+
+      declare <16 x float>  @llvm.vp.maximum.v16f32 (<16 x float> <left_op>, <16 x float> <right_op>, <16 x i1> <mask>, i32 <vector_length>)
+      declare <vscale x 4 x float>  @llvm.vp.maximum.nxv4f32 (<vscale x 4 x float> <left_op>, <vscale x 4 x float> <right_op>, <vscale x 4 x i1> <mask>, i32 <vector_length>)
+      declare <256 x double>  @llvm.vp.maximum.v256f64 (<256 x double> <left_op>, <256 x double> <right_op>, <256 x i1> <mask>, i32 <vector_length>)
+
+Overview:
+"""""""""
+
+Predicated floating-point maximum of two vectors of floating-point values,
+propagating NaNs and treating -0.0 as less than +0.0.
+
+Arguments:
+""""""""""
+
+The first two operands and the result have the same vector of floating-point type. The
+third operand is the vector mask and has the same number of elements as the
+result vector type. The fourth operand is the explicit vector length of the
+operation.
+
+Semantics:
+""""""""""
+
+The '``llvm.vp.maximum``' intrinsic performs floating-point maximum (:ref:`maximum <i_maximum>`)
+of the first and second vector operand on each enabled lane, the result being 
+NaN if either operand is a NaN. -0.0 is considered to be less than +0.0 for this
+intrinsic. The result on disabled lanes is a :ref:`poison value <poisonvalues>`. 
+The operation is performed in the default floating-point environment.
+
+Examples:
+"""""""""
+
+.. code-block:: llvm
+
+      %r = call <4 x float> @llvm.vp.maximum.v4f32(<4 x float> %a, <4 x float> %b, <4 x i1> %mask, i32 %evl)
+      ;; For all lanes below %evl, %r is lane-wise equivalent to %also.r
+
+      %t = call <4 x float> @llvm.maximum.v4f32(<4 x float> %a, <4 x float> %b, <4 x i1> %mask, i32 %evl)
+      %also.r = select <4 x i1> %mask, <4 x float> %t, <4 x float> poison
+
+
 .. _int_vp_fadd:
 
 '``llvm.vp.fadd.*``' Intrinsics