[llvm] 3a8d7fe - [SimplifyCFG] teach simplifycfg not to introduce ptrtoint for NI pointers

[Valentin Churavy via llvm-commits]

Author: Jameson Nash
Date: 2022-08-15T15:11:48-04:00
New Revision: 3a8d7fe20199aa73590d7a240ac9376624203b7f

URL: https://github.com/llvm/llvm-project/commit/3a8d7fe20199aa73590d7a240ac9376624203b7f
DIFF: https://github.com/llvm/llvm-project/commit/3a8d7fe20199aa73590d7a240ac9376624203b7f.diff

LOG: [SimplifyCFG] teach simplifycfg not to introduce ptrtoint for NI pointers

SimplifyCFG expects to be able to cast both sides to an int, if either side can be case to an int, but this is not desirable or legal, in general, per D104547.

Spotted in https://github.com/JuliaLang/julia/issues/45702

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D128670

Added: 
    llvm/test/Transforms/SimplifyCFG/nonintegral.ll

Modified: 
    llvm/lib/Transforms/Utils/SimplifyCFG.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index 197b0d75d0912..76f09c0bb14d1 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -473,7 +473,8 @@ static bool dominatesMergePoint(Value *V, BasicBlock *BB,
 static ConstantInt *GetConstantInt(Value *V, const DataLayout &DL) {
   // Normal constant int.
   ConstantInt *CI = dyn_cast<ConstantInt>(V);
-  if (CI || !isa<Constant>(V) || !V->getType()->isPointerTy())
+  if (CI || !isa<Constant>(V) || !V->getType()->isPointerTy() ||
+      DL.isNonIntegralPointerType(V->getType()))
     return CI;
 
   // This is some kind of pointer constant. Turn it into a pointer-sized

diff  --git a/llvm/test/Transforms/SimplifyCFG/nonintegral.ll b/llvm/test/Transforms/SimplifyCFG/nonintegral.ll
new file mode 100644
index 0000000000000..7880c6a5e6309
--- /dev/null
+++ b/llvm/test/Transforms/SimplifyCFG/nonintegral.ll
@@ -0,0 +1,28 @@
+; RUN: opt -passes=simplifycfg -S < %s | FileCheck %s
+
+target datalayout = "ni:1"
+
+define void @test_01(i64 addrspace(1)* align 8 %ptr) {
+; CHECK-LABEL: @test_01(
+; CHECK-NOT:   ptrtoint
+; CHECK-NEXT:  icmp eq i64 addrspace(1)* %ptr, null
+; CHECK-NOT:   ptrtoint
+  %cond1 = icmp eq i64 addrspace(1)* %ptr, null
+  %cond2 = icmp eq i64 addrspace(1)* %ptr, null
+  br i1 %cond1, label %true1, label %false1
+
+true1:
+  br i1 %cond2, label %true2, label %false2
+
+false1:
+  store i64 1, i64 addrspace(1)* %ptr, align 8
+  br label %true1
+
+true2:
+  store i64 2, i64 addrspace(1)* %ptr, align 8
+  ret void
+
+false2:
+  store i64 3, i64 addrspace(1)* %ptr, align 8
+  ret void
+}