[llvm] 315e300 - [CodeGenPrepare][RISCV] Remove asserting VH references before erasing the dead GEP

[Yingwei Zheng via llvm-commits]

Author: Yingwei Zheng
Date: 2023-06-18T23:40:47+08:00
New Revision: 315e3001c0ebe1a76c0cb6109d29a3a5e22376de

URL: https://github.com/llvm/llvm-project/commit/315e3001c0ebe1a76c0cb6109d29a3a5e22376de
DIFF: https://github.com/llvm/llvm-project/commit/315e3001c0ebe1a76c0cb6109d29a3a5e22376de.diff

LOG: [CodeGenPrepare][RISCV] Remove asserting VH references before erasing the dead GEP

Fixes issue https://github.com/llvm/llvm-project/issues/63365

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D153194

Added: 
    llvm/test/CodeGen/RISCV/pr63365.ll

Modified: 
    llvm/lib/CodeGen/CodeGenPrepare.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index 0e2793a8c3504..410bfc53d63ab 100644
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -8180,7 +8180,9 @@ bool CodeGenPrepare::optimizeInst(Instruction *I, ModifyDT &ModifiedDT) {
                                         GEPI->getName(), GEPI);
       NC->setDebugLoc(GEPI->getDebugLoc());
       replaceAllUsesWith(GEPI, NC, FreshBBs, IsHugeFunc);
-      GEPI->eraseFromParent();
+      RecursivelyDeleteTriviallyDeadInstructions(
+          GEPI, TLInfo, nullptr,
+          [&](Value *V) { removeAllAssertingVHReferences(V); });
       ++NumGEPsElim;
       optimizeInst(NC, ModifiedDT);
       return true;

diff  --git a/llvm/test/CodeGen/RISCV/pr63365.ll b/llvm/test/CodeGen/RISCV/pr63365.ll
new file mode 100644
index 0000000000000..3c7071a315b7a
--- /dev/null
+++ b/llvm/test/CodeGen/RISCV/pr63365.ll
@@ -0,0 +1,25 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=riscv32 | FileCheck %s
+
+ at G = external global i32
+ at G.1 = external global i32
+ at G.2 = external global i64
+ at G.3 = external global i1
+ at G.4 = external global i1
+ at G.5 = external global i8
+
+define void @f() {
+; CHECK-LABEL: f:
+; CHECK:       # %bb.0: # %BB
+; CHECK-NEXT:    addi sp, sp, -16
+; CHECK-NEXT:    .cfi_def_cfa_offset 16
+; CHECK-NEXT:    addi sp, sp, 16
+; CHECK-NEXT:    ret
+BB:
+  %A1 = alloca ptr, align 8
+  %G4 = getelementptr i1, ptr %A1, i32 65536
+  %G = getelementptr i1, ptr %A1, i64 4294967296
+  %L2 = load i8, ptr %G4, align 1
+  store i8 poison, ptr %G, align 1
+  ret void
+}