[DSE] Only consider provenance captures

As a memory analysis, DSE only captures about provenance captures.
Address captures can be ignored as they cannot be used to read
or modify memory.

Author: nikic

llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp

@@ -1213,7 +1213,8 @@ struct DSEState {
 
     auto I = InvisibleToCallerAfterRet.insert({V, false});
     if (I.second && isInvisibleToCallerOnUnwind(V) && isNoAliasCall(V))
-      I.first->second = !PointerMayBeCaptured(V, /*ReturnCaptures=*/true);
+      I.first->second = capturesNothing(PointerMayBeCaptured(
+          V, /*ReturnCaptures=*/true, CaptureComponents::Provenance));
     return I.first->second;
   }
 
@@ -1230,7 +1231,8 @@ struct DSEState {
       // with the killing MemoryDef. But we refrain from doing so for now to
       // limit compile-time and this does not cause any changes to the number
       // of stores removed on a large test set in practice.
-      I.first->second = PointerMayBeCaptured(V, /*ReturnCaptures=*/false);
+      I.first->second = capturesAnything(PointerMayBeCaptured(
+          V, /*ReturnCaptures=*/false, CaptureComponents::Provenance));
     return !I.first->second;
   }
 

llvm/test/Transforms/DeadStoreElimination/assume.ll

@@ -8,7 +8,6 @@ define void @f() {
 ; CHECK-NEXT:    [[TMP1:%.*]] = call noalias ptr @_Znwm(i64 32)
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp ugt ptr [[TMP1]], @global
 ; CHECK-NEXT:    call void @llvm.assume(i1 [[TMP2]])
-; CHECK-NEXT:    store i8 0, ptr [[TMP1]], align 1
 ; CHECK-NEXT:    ret void
 ;
   %tmp1 = call noalias ptr @_Znwm(i64 32)
@@ -23,7 +22,6 @@ define void @f2() {
 ; CHECK-NEXT:    [[TMP1:%.*]] = call noalias ptr @_Znwm(i64 32)
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp ugt ptr [[TMP1]], @global
 ; CHECK-NEXT:    call void @llvm.assume(i1 [[TMP2]])
-; CHECK-NEXT:    store i8 0, ptr [[TMP1]], align 1
 ; CHECK-NEXT:    call void @quux(ptr @global)
 ; CHECK-NEXT:    ret void
 ;

llvm/test/Transforms/DeadStoreElimination/simple.ll

@@ -322,7 +322,6 @@ define void @malloc_address_only_escape() {
 ; CHECK-LABEL: @malloc_address_only_escape(
 ; CHECK-NEXT:    [[M:%.*]] = call ptr @malloc(i64 24)
 ; CHECK-NEXT:    call void @use.ptr(ptr captures(address) [[M]])
-; CHECK-NEXT:    store i8 0, ptr [[M]], align 1
 ; CHECK-NEXT:    ret void
 ;
   %m = call ptr @malloc(i64 24)