[llvm] cc6a864 - [RISCV][VLOPT] Add support for vfrec7.v (#146918)

[via llvm-commits]

Author: Mikhail R. Gadelha
Date: 2025-07-04T12:35:06-03:00
New Revision: cc6a864788ff4b2687f66e4f6ddef7272e82d06d

URL: https://github.com/llvm/llvm-project/commit/cc6a864788ff4b2687f66e4f6ddef7272e82d06d
DIFF: https://github.com/llvm/llvm-project/commit/cc6a864788ff4b2687f66e4f6ddef7272e82d06d.diff

LOG: [RISCV][VLOPT] Add support for vfrec7.v (#146918)

Add support for the vfrec7.v instruction in the RISC-V VLOptimizer.

Added: 
    

Modified: 
    llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
    llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll

Removed: 
    


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diff  --git a/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp b/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
index a406bada6b1e4..2d9f38221d424 100644
--- a/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
+++ b/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
@@ -1107,6 +1107,8 @@ static bool isSupportedInstr(const MachineInstr &MI) {
   case RISCV::VFSQRT_V:
   // Vector Floating-Point Reciprocal Square-Root Estimate Instruction
   case RISCV::VFRSQRT7_V:
+  // Vector Floating-Point Reciprocal Estimate Instruction
+  case RISCV::VFREC7_V:
   // Vector Floating-Point MIN/MAX Instructions
   case RISCV::VFMIN_VF:
   case RISCV::VFMIN_VV:

diff  --git a/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll b/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll
index c272297b41c94..0aa0cbceefc76 100644
--- a/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll
+++ b/llvm/test/CodeGen/RISCV/rvv/vl-opt-instrs.ll
@@ -5380,12 +5380,11 @@ define <vscale x 4 x double> @vfrec7(<vscale x 4 x float> %a) {
 ;
 ; VLOPT-LABEL: vfrec7:
 ; VLOPT:       # %bb.0:
-; VLOPT-NEXT:    vsetivli zero, 7, e32, m2, ta, ma
+; VLOPT-NEXT:    vsetivli zero, 6, e32, m2, ta, ma
 ; VLOPT-NEXT:    vmv2r.v v12, v8
 ; VLOPT-NEXT:    fsrmi a0, 0
 ; VLOPT-NEXT:    vfrec7.v v14, v8
 ; VLOPT-NEXT:    fsrm a0
-; VLOPT-NEXT:    vsetivli zero, 6, e32, m2, ta, ma
 ; VLOPT-NEXT:    vfwmacc.vv v8, v12, v14
 ; VLOPT-NEXT:    ret
   %1 = call <vscale x 4 x float> @llvm.riscv.vfrec7.nxv4f32(<vscale x 4 x float> poison, <vscale x 4 x float> %a, iXLen 0, iXLen 7)