Merging r298177:

------------------------------------------------------------------------
r298177 | niravd | 2017-03-17 20:43:39 -0400 (Fri, 17 Mar 2017) | 7 lines

[X86] Add NumRegisterParameters Module Flag.

Reviewers: rnk, mkuper

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27051
------------------------------------------------------------------------

git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_40@304294 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CodeGenModule.cpp

@@ -159,6 +159,12 @@ CodeGenModule::CodeGenModule(ASTContext &C, const HeaderSearchOptions &HSO,
   // CoverageMappingModuleGen object.
   if (CodeGenOpts.CoverageMapping)
     CoverageMapping.reset(new CoverageMappingModuleGen(*this, *CoverageInfo));
+
+  // Record mregparm value now so it is visible through rest of codegen.
+  if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
+    getModule().addModuleFlag(llvm::Module::Error, "NumRegisterParameters",
+                              CodeGenOpts.NumRegisterParameters);
+
 }
 
 CodeGenModule::~CodeGenModule() {}
@@ -416,6 +422,7 @@ void CodeGenModule::Release() {
       (Context.getLangOpts().Modules || !LinkerOptionsMetadata.empty())) {
     EmitModuleLinkOptions();
   }
+
   if (CodeGenOpts.DwarfVersion) {
     // We actually want the latest version when there are conflicts.
     // We can change from Warning to Latest if such mode is supported.

test/CodeGen/pr3997.c

+// RUN: %clang_cc1 %s -triple i386-unknown-linux-gnu -mregparm 3 -emit-llvm -o - | FileCheck %s
+
+void *memcpy(void *dest, const void *src, unsigned int n);
+
+void use_builtin_memcpy(void *dest, const void *src, unsigned int n) {
+  __builtin_memcpy(dest, src, n);
+}
+
+void use_memcpy(void *dest, const void *src, unsigned int n) {
+  memcpy(dest, src, n);
+}
+
+//CHECK: !{i32 1, !"NumRegisterParameters", i32 3}

test/Headers/altivec-header.c

@@ -9,4 +9,4 @@
 
 // CHECK: target triple = "powerpc64-
 // CHECK-NEXT: {{^$}}
-// CHECK-NEXT: llvm.ident
+// CHECK-NEXT: {{llvm\..*}}