[llvm-branch-commits] [llvm] release/23.x: [SCCP] Fix missing worklist push for recursive calls that update lattice values (#219826) (PR #219832)

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llvmorg-github-actions[bot] wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-function-specialization

Author: llvmbot

<details>
<summary>Changes</summary>

Backport 88f3a791ddb3886cb6fa8d8df1c19e821b7a49b2

Requested by: @<!-- -->dtcxzyw

---
Full diff: https://github.com/llvm/llvm-project/pull/219832.diff


2 Files Affected:

- (modified) llvm/lib/Transforms/Utils/SCCPSolver.cpp (+1-1) 
- (added) llvm/test/Transforms/SCCP/ipsccp-recursive-arg-update.ll (+37) 


``````````diff
diff --git a/llvm/lib/Transforms/Utils/SCCPSolver.cpp b/llvm/lib/Transforms/Utils/SCCPSolver.cpp
index f7e28132ec65c..054d1765f7ebc 100644
--- a/llvm/lib/Transforms/Utils/SCCPSolver.cpp
+++ b/llvm/lib/Transforms/Utils/SCCPSolver.cpp
@@ -1070,7 +1070,7 @@ void SCCPInstVisitor::pushToWorkList(Instruction *I) {
   // same blocks that are after the current one, as they will be visited
   // anyway. We do have to push updates to earlier instructions (e.g. phi
   // nodes or loads of tracked globals).
-  if (CurI && I->getParent() == CurI->getParent() && !I->comesBefore(CurI))
+  if (CurI && I->getParent() == CurI->getParent() && CurI->comesBefore(I))
     return;
   // Only push instructions in already visited blocks. Otherwise we'll handle
   // it when we visit the block for the first time.
diff --git a/llvm/test/Transforms/SCCP/ipsccp-recursive-arg-update.ll b/llvm/test/Transforms/SCCP/ipsccp-recursive-arg-update.ll
new file mode 100644
index 0000000000000..750677077ea1e
--- /dev/null
+++ b/llvm/test/Transforms/SCCP/ipsccp-recursive-arg-update.ll
@@ -0,0 +1,37 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -S -passes=ipsccp < %s | FileCheck %s
+
+define void @caller() {
+; CHECK-LABEL: define void @caller() {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CALL:%.*]] = call i32 @f2(i8 0, i8 0)
+; CHECK-NEXT:    ret void
+;
+entry:
+  %call = call i32 @f2(i8 0, i8 0)
+  ret void
+}
+
+define internal i32 @f2(i8 %a0, i8 %a1) {
+; CHECK-LABEL: define internal i32 @f2(
+; CHECK-SAME: i8 range(i8 -9, 1) [[A0:%.*]], i8 range(i8 -9, 1) [[A1:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP_NOT_NOT:%.*]] = icmp eq i8 [[A0]], -9
+; CHECK-NEXT:    br i1 [[CMP_NOT_NOT]], label [[COMMON_RET1:%.*]], label [[IF_THEN3:%.*]]
+; CHECK:       common.ret1:
+; CHECK-NEXT:    ret i32 poison
+; CHECK:       if.then3:
+; CHECK-NEXT:    [[CALL:%.*]] = call i32 @f2(i8 [[A1]], i8 -9)
+; CHECK-NEXT:    ret i32 poison
+;
+entry:
+  %cmp.not.not = icmp eq i8 %a0, -9
+  br i1 %cmp.not.not, label %common.ret1, label %if.then3
+
+common.ret1:                                      ; preds = %entry
+  ret i32 0
+
+if.then3:                                         ; preds = %entry
+  %call = call i32 @f2(i8 %a1, i8 -9)
+  ret i32 %call
+}

``````````

</details>


https://github.com/llvm/llvm-project/pull/219832