From cf54ca458afff1f7827bfbbc939429a00496c4f7 Mon Sep 17 00:00:00 2001
From: Tom Stellard <tstellar@redhat.com>
Date: Tue, 18 Aug 2020 10:54:49 -0700
Subject: [PATCH] [PowerPC] PPCBoolRetToInt: Skip translation if there is
 ConstantExpr

PPCBoolRetToInt collects PHI, Argument, Call and Constant defs related to an `i1` value which later is translated to an `i32`/`i64` value. The `translate` method expects an `i1` value. However, if the `Constant` is a `ConstantExpr`, the type of the `ConstantExpr` might not be `i1`.

Fixes https://bugs.llvm.org/show_bug.cgi?id=46923 which causes ICE
```
llvm-project/llvm/lib/IR/Constants.cpp:1924: static llvm::Constant *llvm::ConstantExpr::getZExt(llvm::Constant *, llvm::Type *, bool): Assertion `C->getType()->getScalarSizeInBits() < Ty->getScalarSizeInBits()&& "SrcTy must be smaller than DestTy for ZExt!"' failed.
```

Differential Revision: https://reviews.llvm.org/D85007
---
 llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp |  8 ++++--
 llvm/test/CodeGen/PowerPC/pr46923.ll        | 31 +++++++++++++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)
 create mode 100644 llvm/test/CodeGen/PowerPC/pr46923.ll

diff --git a/llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp b/llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp
index 2259a29f838..cfe3b3ce2e9 100644
--- a/llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp
+++ b/llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp
@@ -90,6 +90,9 @@ class PPCBoolRetToInt : public FunctionPass {
 
   // Translate a i1 value to an equivalent i32/i64 value:
   Value *translate(Value *V) {
+    assert(V->getType() == Type::getInt1Ty(V->getContext()) &&
+           "Expect an i1 value");
+
     Type *IntTy = ST->isPPC64() ? Type::getInt64Ty(V->getContext())
                                 : Type::getInt32Ty(V->getContext());
 
@@ -227,8 +230,9 @@ class PPCBoolRetToInt : public FunctionPass {
     // CallInst. Potentially, bitwise operations (AND, OR, XOR, NOT) and sign
     // extension could also be handled in the future.
     for (Value *V : Defs)
-      if (!isa<PHINode>(V) && !isa<Constant>(V) &&
-          !isa<Argument>(V) && !isa<CallInst>(V))
+      if ((!isa<PHINode>(V) && !isa<Constant>(V) && !isa<Argument>(V) &&
+           !isa<CallInst>(V)) ||
+          isa<ConstantExpr>(V))
         return false;
 
     for (Value *V : Defs)
diff --git a/llvm/test/CodeGen/PowerPC/pr46923.ll b/llvm/test/CodeGen/PowerPC/pr46923.ll
new file mode 100644
index 00000000000..d6f65508848
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/pr46923.ll
@@ -0,0 +1,31 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -verify-machineinstrs -mtriple=powerpc64le-unknown-unknown \
+; RUN:   -ppc-asm-full-reg-names < %s | FileCheck %s
+
+@bar = external constant i64, align 8
+
+define i1 @foo() {
+; CHECK-LABEL: foo:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    crxor 4*cr5+lt, 4*cr5+lt, 4*cr5+lt
+; CHECK-NEXT:    li r3, 0
+; CHECK-NEXT:    li r4, 1
+; CHECK-NEXT:    isel r3, r4, r3, 4*cr5+lt
+; CHECK-NEXT:    blr
+entry:
+  br label %next
+
+next:
+  br i1 undef, label %true, label %false
+
+true:
+  br label %end
+
+false:
+  br label %end
+
+end:
+  %a = phi i1 [ icmp ugt (i64 0, i64 ptrtoint (i64* @bar to i64)), %true ],
+              [ icmp ugt (i64 0, i64 2), %false ]
+  ret i1 %a
+}
-- 
2.18.1