[llvm] r323307 - [GlobalMerge] Don't merge dllexport globals

[Martin Storsjo via llvm-commits]

Author: mstorsjo
Date: Tue Jan 23 22:40:04 2018
New Revision: 323307

URL: http://llvm.org/viewvc/llvm-project?rev=323307&view=rev
Log:
[GlobalMerge] Don't merge dllexport globals

Merging such globals loses the dllexport attribute. Add a test
to check that normal globals still are merged.

Differential Revision: https://reviews.llvm.org/D42127

Added:
    llvm/trunk/test/CodeGen/ARM/global-merge-dllexport.ll
Modified:
    llvm/trunk/lib/CodeGen/GlobalMerge.cpp
    llvm/trunk/test/CodeGen/ARM/global-merge-external.ll

Modified: llvm/trunk/lib/CodeGen/GlobalMerge.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/GlobalMerge.cpp?rev=323307&r1=323306&r2=323307&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/GlobalMerge.cpp (original)
+++ llvm/trunk/lib/CodeGen/GlobalMerge.cpp Tue Jan 23 22:40:04 2018
@@ -577,7 +577,8 @@ bool GlobalMerge::doInitialization(Modul
   for (auto &GV : M.globals()) {
     // Merge is safe for "normal" internal or external globals only
     if (GV.isDeclaration() || GV.isThreadLocal() ||
-        GV.hasSection() || GV.hasImplicitSection())
+        GV.hasSection() || GV.hasImplicitSection() ||
+        GV.hasDLLExportStorageClass())
       continue;
 
     // It's not safe to merge globals that may be preempted

Added: llvm/trunk/test/CodeGen/ARM/global-merge-dllexport.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/global-merge-dllexport.ll?rev=323307&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/global-merge-dllexport.ll (added)
+++ llvm/trunk/test/CodeGen/ARM/global-merge-dllexport.ll Tue Jan 23 22:40:04 2018
@@ -0,0 +1,15 @@
+; RUN: llc < %s -mtriple=thumbv7-win32 -arm-global-merge | FileCheck %s
+
+ at x = global i32 0, align 4
+ at y = dllexport global i32 0, align 4
+
+define void @f1(i32 %a1, i32 %a2) {
+; CHECK: f1:
+; CHECK: movw [[REG1:r[0-9]+]], :lower16:x
+; CHECK: movt [[REG1]], :upper16:x
+  store i32 %a1, i32* @x, align 4
+  store i32 %a2, i32* @y, align 4
+  ret void
+}
+
+; CHECK-NOT: .L_MergedGlobals

Modified: llvm/trunk/test/CodeGen/ARM/global-merge-external.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/global-merge-external.ll?rev=323307&r1=323306&r2=323307&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/global-merge-external.ll (original)
+++ llvm/trunk/test/CodeGen/ARM/global-merge-external.ll Tue Jan 23 22:40:04 2018
@@ -3,6 +3,7 @@
 ; RUN: llc < %s -mtriple=arm-eabi  -arm-global-merge -global-merge-on-external=false | FileCheck %s --check-prefixes=CHECK,CHECK-NO-MERGE
 ; RUN: llc < %s -mtriple=arm-macho -arm-global-merge                                 | FileCheck %s --check-prefixes=CHECK,CHECK-NO-MERGE
 ; RUN: llc < %s -mtriple=arm-eabi  -arm-global-merge -relocation-model=pic           | FileCheck %s --check-prefixes=CHECK,CHECK-NO-MERGE
+; RUN: llc < %s -mtriple=thumbv7-win32 -arm-global-merge                             | FileCheck %s --check-prefixes=CHECK-WIN32
 
 @x = global i32 0, align 4
 @y = global i32 0, align 4
@@ -14,6 +15,9 @@ define void @f1(i32 %a1, i32 %a2) {
 ;CHECK:          [[LABEL1]]:
 ;CHECK-MERGE:    .long .L_MergedGlobals
 ;CHECK-NO-MERGE: .long {{_?x}}
+;CHECK-WIN32:    f1:
+;CHECK-WIN32:    movw [[REG1:r[0-9]+]], :lower16:.L_MergedGlobals
+;CHECK-WIN32:    movt [[REG1]], :upper16:.L_MergedGlobals
   store i32 %a1, i32* @x, align 4
   store i32 %a2, i32* @y, align 4
   ret void
@@ -25,6 +29,9 @@ define void @g1(i32 %a1, i32 %a2) {
 ;CHECK:          [[LABEL2]]:
 ;CHECK-MERGE:    .long .L_MergedGlobals
 ;CHECK-NO-MERGE: .long {{_?y}}
+;CHECK-WIN32:    g1:
+;CHECK-WIN32:    movw [[REG2:r[0-9]+]], :lower16:.L_MergedGlobals
+;CHECK-WIN32:    movt [[REG2]], :upper16:.L_MergedGlobals
   store i32 %a1, i32* @y, align 4
   store i32 %a2, i32* @z, align 4
   ret void
@@ -35,6 +42,7 @@ define void @g1(i32 %a1, i32 %a2) {
 ;CHECK-MERGE:	.type	.L_MergedGlobals,%object
 ;CHECK-MERGE:	.local	.L_MergedGlobals
 ;CHECK-MERGE:	.comm	.L_MergedGlobals,12,4
+;CHECK-WIN32:	.lcomm	.L_MergedGlobals,12,4
 
 ;CHECK-MERGE:	.globl	x
 ;CHECK-MERGE: x = .L_MergedGlobals
@@ -45,3 +53,10 @@ define void @g1(i32 %a1, i32 %a2) {
 ;CHECK-MERGE:	.globl	z
 ;CHECK-MERGE: z = .L_MergedGlobals+8
 ;CHECK-MERGE: .size z, 4
+
+;CHECK-WIN32:	.globl	x
+;CHECK-WIN32: x = .L_MergedGlobals
+;CHECK-WIN32:	.globl	y
+;CHECK-WIN32: y = .L_MergedGlobals+4
+;CHECK-WIN32:	.globl	z
+;CHECK-WIN32: z = .L_MergedGlobals+8