[llvm] f862d62 - llvm-reduce: Fix invalid reduction from breaking phi operands
Matt Arsenault via llvm-commits
llvm-commits at lists.llvm.org
Wed Aug 23 15:54:53 PDT 2023
Author: Matt Arsenault
Date: 2023-08-23T18:54:48-04:00
New Revision: f862d62350aebab1b5839c22f4f5ab8aba3abe02
URL: https://github.com/llvm/llvm-project/commit/f862d62350aebab1b5839c22f4f5ab8aba3abe02
DIFF: https://github.com/llvm/llvm-project/commit/f862d62350aebab1b5839c22f4f5ab8aba3abe02.diff
LOG: llvm-reduce: Fix invalid reduction from breaking phi operands
Fix "PHI node has multiple entries for the same basic block with
different incoming values!" when running operands-to-args.
https://reviews.llvm.org/D158422
Added:
llvm/test/tools/llvm-reduce/operands-to-args-phi.ll
Modified:
llvm/tools/llvm-reduce/deltas/ReduceOperandsToArgs.cpp
Removed:
################################################################################
diff --git a/llvm/test/tools/llvm-reduce/operands-to-args-phi.ll b/llvm/test/tools/llvm-reduce/operands-to-args-phi.ll
new file mode 100644
index 00000000000000..9b94861e1f3560
--- /dev/null
+++ b/llvm/test/tools/llvm-reduce/operands-to-args-phi.ll
@@ -0,0 +1,73 @@
+; RUN: llvm-reduce --abort-on-invalid-reduction %s -o %t --delta-passes=operands-to-args --test FileCheck --test-arg %s --test-arg --check-prefix=INTERESTING --test-arg --input-file
+; RUN: FileCheck -check-prefix=RESULT %s < %t
+
+; Make sure an invalid reduction isn't hit from only replacing one of
+; the values when a predecessor is listed multiple times in a phi.
+
+
+; RESULT: define void @fn(i1 %cmp11, i8 %p.2, i8 %k.2, i8 %p.4, i8 %k.0, i8 %k.4, i8 %p.0, i1 %tobool30, i8 %spec.select, i8 %spec.select1)
+
+; RESULT: for.cond:
+; RESULT-NEXT: %p.01 = phi i8 [ 0, %entry ], [ %p.2, %for.inc ]
+; RESULT-NEXT: %k.02 = phi i8 [ 0, %entry ], [ %k.2, %for.inc ]
+
+; RESULT: if.end26:
+; RESULT-NEXT: %p.1 = phi i8 [ %p.4, %for.cond35 ], [ %k.0, %if.end ]
+; RESULT-NEXT: %k.1 = phi i8 [ %k.4, %for.cond35 ], [ 0, %if.end ]
+
+; RESULT: for.inc:
+; RESULT-NEXT: %p.26 = phi i8 [ %spec.select, %if.end26 ], [ poison, %if.then13 ], [ %spec.select, %if.end26 ]
+; RESULT-NEXT: %k.27 = phi i8 [ %spec.select1, %if.end26 ], [ 0, %if.then13 ], [ %spec.select1, %if.end26 ]
+
+
+; RESULT: for.cond35:
+; RESULT-NEXT: %p.48 = phi i8 [ 0, %if.then ], [ %k.0, %if.then13 ]
+; RESULT-NEXT: %k.49 = phi i8 [ %k.0, %if.then ], [ 0, %if.then13 ]
+
+define void @fn(i1 %cmp11) {
+entry:
+ br label %for.cond
+
+for.cond: ; preds = %for.inc, %entry
+ %p.0 = phi i8 [ 0, %entry ], [ %p.2, %for.inc ]
+ %k.0 = phi i8 [ 0, %entry ], [ %k.2, %for.inc ]
+ br i1 %cmp11, label %if.then, label %if.end
+
+if.then: ; preds = %for.cond
+ br label %for.cond35
+
+if.end: ; preds = %for.cond
+ br i1 %cmp11, label %if.then13, label %if.end26
+
+if.then13: ; preds = %if.end
+ br i1 %cmp11, label %for.inc, label %for.cond35
+
+if.end26: ; preds = %for.cond35, %if.end
+ ; INTERESTING: %p.1 = phi i8
+ ; INTERESTING: %k.1 = phi i8
+
+ %p.1 = phi i8 [ %p.4, %for.cond35 ], [ %k.0, %if.end ]
+ %k.1 = phi i8 [ %k.4, %for.cond35 ], [ 0, %if.end ]
+ %tobool30 = icmp ne i8 %p.0, 0
+ %spec.select = select i1 false, i8 0, i8 %p.1
+ %spec.select1 = select i1 %tobool30, i8 %k.1, i8 0
+ br i1 false, label %for.inc, label %for.inc
+
+; INTERESTING: {{^}}for.inc:
+; INTERESTING: phi i8
+; INTERESTING-SAME: [ %spec.select{{[0-9]*}}, %if.end26 ]
+
+; INTERESTING: phi i8
+; INTERESTING-SAME: [ %spec.select{{[0-9]*}}, %if.end26 ]
+for.inc: ; preds = %if.end26, %if.end26, %if.then13
+ %p.2 = phi i8 [ %spec.select, %if.end26 ], [ poison, %if.then13 ], [ %spec.select, %if.end26 ]
+ %k.2 = phi i8 [ %spec.select1, %if.end26 ], [ 0, %if.then13 ], [ %spec.select1, %if.end26 ]
+ %0 = load i32, ptr null, align 4
+ br label %for.cond
+
+for.cond35: ; preds = %if.then13, %if.then
+ %p.4 = phi i8 [ 0, %if.then ], [ %k.0, %if.then13 ]
+ %k.4 = phi i8 [ %k.0, %if.then ], [ 0, %if.then13 ]
+ %tobool36 = icmp eq i32 0, 0
+ br label %if.end26
+}
diff --git a/llvm/tools/llvm-reduce/deltas/ReduceOperandsToArgs.cpp b/llvm/tools/llvm-reduce/deltas/ReduceOperandsToArgs.cpp
index 0f949ab1fe8977..30758aea1b4eda 100644
--- a/llvm/tools/llvm-reduce/deltas/ReduceOperandsToArgs.cpp
+++ b/llvm/tools/llvm-reduce/deltas/ReduceOperandsToArgs.cpp
@@ -160,7 +160,14 @@ static void substituteOperandWithArgument(Function *OldF,
for (Use *Op : OpsToReplace) {
Value *NewArg = OldValMap.lookup(Op->get());
auto *NewUser = cast<Instruction>(VMap.lookup(Op->getUser()));
- NewUser->setOperand(Op->getOperandNo(), NewArg);
+
+ if (PHINode *NewPhi = dyn_cast<PHINode>(NewUser)) {
+ PHINode *OldPhi = cast<PHINode>(Op->getUser());
+ BasicBlock *OldBB = OldPhi->getIncomingBlock(*Op);
+ NewPhi->setIncomingValueForBlock(cast<BasicBlock>(VMap.lookup(OldBB)),
+ NewArg);
+ } else
+ NewUser->setOperand(Op->getOperandNo(), NewArg);
}
// Replace all OldF uses with NewF.
More information about the llvm-commits
mailing list