[llvm] faf848a - [Inline] Fix in handling of ptrtoint in InlineCost

[Mikael Holmen via llvm-commits]

Author: Mikael Holmen
Date: 2020-11-23T14:33:06+01:00
New Revision: faf848ac321801ba92b1d3038fccc84988d46ac8

URL: https://github.com/llvm/llvm-project/commit/faf848ac321801ba92b1d3038fccc84988d46ac8
DIFF: https://github.com/llvm/llvm-project/commit/faf848ac321801ba92b1d3038fccc84988d46ac8.diff

LOG: [Inline] Fix in handling of ptrtoint in InlineCost

ConstantOffsetPtrs contains mappings from a Value to a base pointer and
an offset. The offset is typed and has a size, and at least when dealing
with ptrtoint, it could happen that we had a mapping from a ptrtoint
with type i32 to an offset with type i16. This could later cause
problems, showing up in PR 47969 and PR 38500.

In PR 47969 we ended up in an assert complaining that trunc i16 to i16
is invalid and in Pr 38500 that a cmp on an i32 and i16 value isn't
valid.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D90610

Added: 
    llvm/test/Transforms/Inline/inline-ptrtoint-different-sizes.ll

Modified: 
    llvm/lib/Analysis/InlineCost.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/InlineCost.cpp b/llvm/lib/Analysis/InlineCost.cpp
index 8a4b779e5084..80be0040e7b3 100644
--- a/llvm/lib/Analysis/InlineCost.cpp
+++ b/llvm/lib/Analysis/InlineCost.cpp
@@ -1101,7 +1101,7 @@ bool CallAnalyzer::visitPtrToInt(PtrToIntInst &I) {
   // integer is large enough to represent the pointer.
   unsigned IntegerSize = I.getType()->getScalarSizeInBits();
   unsigned AS = I.getOperand(0)->getType()->getPointerAddressSpace();
-  if (IntegerSize >= DL.getPointerSizeInBits(AS)) {
+  if (IntegerSize == DL.getPointerSizeInBits(AS)) {
     std::pair<Value *, APInt> BaseAndOffset =
         ConstantOffsetPtrs.lookup(I.getOperand(0));
     if (BaseAndOffset.first)

diff  --git a/llvm/test/Transforms/Inline/inline-ptrtoint-
diff erent-sizes.ll b/llvm/test/Transforms/Inline/inline-ptrtoint-
diff erent-sizes.ll
new file mode 100644
index 000000000000..b412504a800c
--- /dev/null
+++ b/llvm/test/Transforms/Inline/inline-ptrtoint-
diff erent-sizes.ll
@@ -0,0 +1,40 @@
+; RUN: opt < %s -inline -S | FileCheck %s
+
+; InlineCost used to have problems with the ptrtoint, leading to
+; crashes when visiting the trunc in pr48908_help and the icmp in
+; pr38500_help.
+
+target datalayout = "p:16:16"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @pr48980_help(i16* %p) {
+  %cast = ptrtoint i16* %p to i32
+  %sub = sub i32 %cast, %cast
+  %conv = trunc i32 %sub to i16
+  ret void
+}
+
+define void @pr48980(i16* %x) {
+  call void @pr48980_help(i16* %x)
+  ret void
+}
+
+; CHECK-LABEL: @pr48980(i16* %x)
+; CHECK-NOT:     call
+; CHECK:         ret void
+
+define void @pr38500_help(i16* %p) {
+  %cast = ptrtoint i16* %p to i32
+  %sub = sub i32 %cast, %cast
+  %cmp = icmp eq i32 %sub, 0
+  ret void
+}
+
+define void @pr38500(i16* %x) {
+  call void @pr38500_help(i16* %x)
+  ret void
+}
+
+; CHECK-LABEL: @pr38500(i16* %x)
+; CHECK-NOT:     call
+; CHECK:         ret void