[clang/Basic] Make TargetInfo.h not use DataLayout again

Reverts parts of https://reviews.llvm.org/D17183, but keeps the
resetDataLayout() API and adds an assert that checks that datalayout string and
user label prefix are in sync.

Approach 1 in https://reviews.llvm.org/D17183#2653279
Reduces number of TUs build for 'clang-format' from 689 to 575.

I also implemented approach 2 in D100764. If someone feels motivated
to make us use DataLayout more, it's easy to revert this change here
and go with D100764 instead. I don't plan on doing more work in this
area though, so I prefer going with the smaller, more self-consistent change.

Differential Revision: https://reviews.llvm.org/D100776

1 files changed, 4 insertions, 3 deletions

diff --git a/clang/lib/Basic/TargetInfo.cpp b/clang/lib/Basic/TargetInfo.cpp
index 1783da8..a431ec1 100644
--- a/clang/lib/Basic/TargetInfo.cpp
+++ b/clang/lib/Basic/TargetInfo.cpp
@@ -17,7 +17,6 @@
 #include "clang/Basic/LangOptions.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/STLExtras.h"
-#include "llvm/IR/DataLayout.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/TargetParser.h"
 #include <cstdlib>
@@ -114,6 +113,7 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
   LongDoubleFormat = &llvm::APFloat::IEEEdouble();
   Float128Format = &llvm::APFloat::IEEEquad();
   MCountName = "mcount";
+  UserLabelPrefix = "_";
   RegParmMax = 0;
   SSERegParmMax = 0;
   HasAlignMac68kSupport = false;
@@ -149,8 +149,9 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
 // Out of line virtual dtor for TargetInfo.
 TargetInfo::~TargetInfo() {}
 
-void TargetInfo::resetDataLayout(StringRef DL) {
-  DataLayout.reset(new llvm::DataLayout(DL));
+void TargetInfo::resetDataLayout(StringRef DL, const char *ULP) {
+  DataLayoutString = DL.str();
+  UserLabelPrefix = ULP;
 }
 
 bool