[llvm] 00999fb - [SelectionDAGBuilder] Pass fast math flags to most of VP SDNodes.

[Yeting Kuo via llvm-commits]

Author: Yeting Kuo
Date: 2022-05-18T16:15:47+08:00
New Revision: 00999fb6e14231de14db292510c854e1bf3baded

URL: https://github.com/llvm/llvm-project/commit/00999fb6e14231de14db292510c854e1bf3baded
DIFF: https://github.com/llvm/llvm-project/commit/00999fb6e14231de14db292510c854e1bf3baded.diff

LOG: [SelectionDAGBuilder] Pass fast math flags to most of VP SDNodes.

The patch does not pass math flags to float VPCmpIntrinsics because LLParser
could not identify float VPCmpIntrinsics as FPMathOperators.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D125600

Added: 
    llvm/test/CodeGen/RISCV/pass-fast-math-flags-sdnode.ll

Modified: 
    llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 2e0d050d21b18..bf4e6a6751c35 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -7606,7 +7606,10 @@ void SelectionDAGBuilder::visitVectorPredicationIntrinsic(
 
   switch (Opcode) {
   default: {
-    SDValue Result = DAG.getNode(Opcode, DL, VTs, OpValues);
+    SDNodeFlags SDFlags;
+    if (auto *FPMO = dyn_cast<FPMathOperator>(&VPIntrin))
+      SDFlags.copyFMF(*FPMO);
+    SDValue Result = DAG.getNode(Opcode, DL, VTs, OpValues, SDFlags);
     setValue(&VPIntrin, Result);
     break;
   }

diff  --git a/llvm/test/CodeGen/RISCV/pass-fast-math-flags-sdnode.ll b/llvm/test/CodeGen/RISCV/pass-fast-math-flags-sdnode.ll
new file mode 100644
index 0000000000000..c057aba4f26a1
--- /dev/null
+++ b/llvm/test/CodeGen/RISCV/pass-fast-math-flags-sdnode.ll
@@ -0,0 +1,9 @@
+; REQUIRES: asserts
+; RUN: llc < %s -mtriple=riscv64 -mattr=+v -debug-only=isel -o /dev/null 2>&1                        | FileCheck %s
+declare <vscale x 1 x double> @llvm.vp.fmul.nxv1f64(<vscale x 1 x double> %x, <vscale x 1 x double> %y, <vscale x 1 x i1> %m, i32 %vl)
+
+define <vscale x 1 x double> @foo(<vscale x 1 x double> %x, <vscale x 1 x double> %y, <vscale x 1 x double> %z, <vscale x 1 x i1> %m, i32 %vl) {
+; CHECK:      t14: nxv1f64 = vp_fmul nnan ninf nsz arcp contract afn reassoc t2, t4, t8, t13
+  %1 = call fast <vscale x 1 x double> @llvm.vp.fmul.nxv1f64(<vscale x 1 x double> %x, <vscale x 1 x double> %y, <vscale x 1 x i1> %m, i32 %vl)
+  ret <vscale x 1 x double> %1
+}