[llvm] 1616a75 - X86: Use use_instructions in CompressEVEX cross-block check (#219408)

[via llvm-commits]

Author: Matt Arsenault
Date: 2026-08-28T08:28:30Z
New Revision: 1616a75cd51165f365dd8f403e4398169e31e34f

URL: https://github.com/llvm/llvm-project/commit/1616a75cd51165f365dd8f403e4398169e31e34f
DIFF: https://github.com/llvm/llvm-project/commit/1616a75cd51165f365dd8f403e4398169e31e34f.diff

LOG: X86: Use use_instructions in CompressEVEX cross-block check (#219408)

The loop only checks the using instruction's parent block, so iterate
use_instructions() instead of the operands and checking their parents.

Co-authored-by: Claude (Claude-Opus-4.8) <noreply at anthropic.com>

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86CompressEVEX.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/X86/X86CompressEVEX.cpp b/llvm/lib/Target/X86/X86CompressEVEX.cpp
index be02c6375c0b5..2c408851975e8 100644
--- a/llvm/lib/Target/X86/X86CompressEVEX.cpp
+++ b/llvm/lib/Target/X86/X86CompressEVEX.cpp
@@ -372,8 +372,8 @@ static bool tryCompressVPMOVPattern(MachineInstr &MI, MachineBasicBlock &MBB,
     return false;
 
   // Check if MaskReg is used in any other basic blocks
-  for (const MachineOperand &MO : MRI->use_operands(MaskReg))
-    if (MO.getParent()->getParent() != &MBB)
+  for (const MachineInstr &UseMI : MRI->use_instructions(MaskReg))
+    if (UseMI.getParent() != &MBB)
       return false;
 
   // Apply the transformation