[llvm] 42e7796 - [ARM] Add a comment about fixupImmediateBr updaing ImmBranches. NFC

[David Green via llvm-commits]

Author: David Green
Date: 2025-07-01T15:01:25+01:00
New Revision: 42e779692027e1bdcb8085b37b428011328c43c8

URL: https://github.com/llvm/llvm-project/commit/42e779692027e1bdcb8085b37b428011328c43c8
DIFF: https://github.com/llvm/llvm-project/commit/42e779692027e1bdcb8085b37b428011328c43c8.diff

LOG: [ARM] Add a comment about fixupImmediateBr updaing ImmBranches. NFC

To prevent people from modernizing the loop, add a comment that
fixupImmediateBr can append to ImmBranches.

Added: 
    

Modified: 
    llvm/lib/Target/ARM/ARMConstantIslandPass.cpp

Removed: 
    


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diff  --git a/llvm/lib/Target/ARM/ARMConstantIslandPass.cpp b/llvm/lib/Target/ARM/ARMConstantIslandPass.cpp
index ca3dc15ff3ad6..ef690838f0f3b 100644
--- a/llvm/lib/Target/ARM/ARMConstantIslandPass.cpp
+++ b/llvm/lib/Target/ARM/ARMConstantIslandPass.cpp
@@ -476,8 +476,10 @@ bool ARMConstantIslands::runOnMachineFunction(MachineFunction &mf) {
 
     LLVM_DEBUG(dbgs() << "Beginning BR iteration #" << NoBRIters << '\n');
     bool BRChange = false;
-    for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i)
+    for (unsigned i = 0, e = ImmBranches.size(); i != e; ++i) {
+      // Note: fixupImmediateBr can append to ImmBranches.
       BRChange |= fixupImmediateBr(ImmBranches[i]);
+    }
     if (BRChange && ++NoBRIters > 30)
       report_fatal_error("Branch Fix Up pass failed to converge!");
     LLVM_DEBUG(dumpBBs());