[llvm] [RISCV][VLOP][NFC] Remove outdated FIXME comments related to supported instructions (PR #156126)

[Min-Yih Hsu via llvm-commits]

https://github.com/mshockwave created https://github.com/llvm/llvm-project/pull/156126

Remove several FIXME comments in `isSupportedInstr` for opcodes that were already implemented. Also moved switch cases for add-carry/sub-borrow instructions together.

NFC.

>From 7afccb5c80447983dec56bdbe039624829da69f1 Mon Sep 17 00:00:00 2001
From: Min-Yih Hsu <min.hsu at sifive.com>
Date: Fri, 29 Aug 2025 16:31:10 -0700
Subject: [PATCH] [RISCV][VLOP][NFC] Remove outdated FIXME comments

---
 llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp b/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
index 01aef86ee7a4b..9b70eb6c25b12 100644
--- a/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
+++ b/llvm/lib/Target/RISCV/RISCVVLOptimizer.cpp
@@ -900,13 +900,6 @@ static bool isSupportedInstr(const MachineInstr &MI) {
   case RISCV::VSEXT_VF4:
   case RISCV::VZEXT_VF8:
   case RISCV::VSEXT_VF8:
-  // Vector Integer Add-with-Carry / Subtract-with-Borrow Instructions
-  // FIXME: Add support
-  case RISCV::VMADC_VV:
-  case RISCV::VMADC_VI:
-  case RISCV::VMADC_VX:
-  case RISCV::VMSBC_VV:
-  case RISCV::VMSBC_VX:
   // Vector Narrowing Integer Right Shift Instructions
   case RISCV::VNSRL_WX:
   case RISCV::VNSRL_WI:
@@ -993,6 +986,11 @@ static bool isSupportedInstr(const MachineInstr &MI) {
   case RISCV::VSBC_VXM:
   case RISCV::VMSBC_VVM:
   case RISCV::VMSBC_VXM:
+  case RISCV::VMADC_VV:
+  case RISCV::VMADC_VI:
+  case RISCV::VMADC_VX:
+  case RISCV::VMSBC_VV:
+  case RISCV::VMSBC_VX:
   // Vector Widening Integer Multiply-Add Instructions
   case RISCV::VWMACCU_VV:
   case RISCV::VWMACCU_VX:
@@ -1001,10 +999,7 @@ static bool isSupportedInstr(const MachineInstr &MI) {
   case RISCV::VWMACCSU_VV:
   case RISCV::VWMACCSU_VX:
   case RISCV::VWMACCUS_VX:
-  // Vector Integer Merge Instructions
-  // FIXME: Add support
   // Vector Integer Move Instructions
-  // FIXME: Add support
   case RISCV::VMV_V_I:
   case RISCV::VMV_V_X:
   case RISCV::VMV_V_V: