[x32/NaCl] Check if method pointers straddle an eightbyte to classify Hi
Summary:
Currently, with struct my_struct { int x; method_ptr y; };
a call to foo(my_struct s) may end up dropping the last 4 bytes
of the method pointer for x86_64 NaCl and x32.
When checking Has64BitPointers, also check if the method pointer
straddles an eightbyte boundary and classify Hi as well as Lo if needed.
Test Plan: test/CodeGenCXX/x86_64-arguments-nacl-x32.cpp
Reviewers: dschuff, pavel.v.chupin
Subscribers: jfb
Differential Revision: http://reviews.llvm.org/D5555
llvm-svn: 218889
diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 2b62d99..49c6626 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -1695,10 +1695,25 @@
}
if (Ty->isMemberPointerType()) {
- if (Ty->isMemberFunctionPointerType() && Has64BitPointers)
- Lo = Hi = Integer;
- else
+ if (Ty->isMemberFunctionPointerType()) {
+ if (Has64BitPointers) {
+ // If Has64BitPointers, this is an {i64, i64}, so classify both
+ // Lo and Hi now.
+ Lo = Hi = Integer;
+ } else {
+ // Otherwise, with 32-bit pointers, this is an {i32, i32}. If that
+ // straddles an eightbyte boundary, Hi should be classified as well.
+ uint64_t EB_FuncPtr = (OffsetBase) / 64;
+ uint64_t EB_ThisAdj = (OffsetBase + 64 - 1) / 64;
+ if (EB_FuncPtr != EB_ThisAdj) {
+ Lo = Hi = Integer;
+ } else {
+ Current = Integer;
+ }
+ }
+ } else {
Current = Integer;
+ }
return;
}