[PATCH] D121580: [SCCP] Fix crash when function arg is a unused basic block's address

[chenglin.bi via Phabricator via llvm-commits]

bcl5980 created this revision.
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For now if Solver never touch a basic block, DTU will erase the basic block even if the basic block address is referenced by function args.
So check the kernel arg is block address or not, if it is we need to mark the basic block executable.

Fix #54238, #54251


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D121580

Files:
  llvm/lib/Transforms/Utils/SCCPSolver.cpp
  llvm/test/Transforms/SCCP/issue54238.ll


Index: llvm/test/Transforms/SCCP/issue54238.ll
===================================================================
--- /dev/null
+++ llvm/test/Transforms/SCCP/issue54238.ll
@@ -0,0 +1,18 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-attributes
+; RUN: opt -passes=ipsccp -S %s | FileCheck %s
+; https://github.com/llvm/llvm-project/issues/54238
+
+define i32 @main() {
+  call void @set_return_addr(i64* bitcast (i8* blockaddress(@main, %redirected) to i64*))
+  ret i32 0
+
+redirected:
+  ret i32 0
+}
+
+define internal void @set_return_addr(i64* %addr) {
+  %addr.addr = alloca i64*, i32 0, align 8
+; CHECK: redirected
+  store i64* %addr, i64** %addr.addr, align 8
+  ret void
+}
Index: llvm/lib/Transforms/Utils/SCCPSolver.cpp
===================================================================
--- llvm/lib/Transforms/Utils/SCCPSolver.cpp
+++ llvm/lib/Transforms/Utils/SCCPSolver.cpp
@@ -1249,6 +1249,14 @@
       if (AI->hasByValAttr() && !F->onlyReadsMemory()) {
         markOverdefined(&*AI);
         continue;
+      } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(CAI)) {
+        markBlockExecutable(BA->getBasicBlock());
+      } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CAI)) {
+        for (Value *Op : CE->operands()) {
+          const BlockAddress *BA = dyn_cast<BlockAddress>(Op);
+          if (BA != nullptr)
+            markBlockExecutable(BA->getBasicBlock());
+        }
       }
 
       if (auto *STy = dyn_cast<StructType>(AI->getType())) {


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