Extend global merge pass to optionally consider global constant variables.

Also add some checks to not merge globals used within landing pad instructions or marked as "used".

llvm-svn: 177331

1 files changed, 52 insertions, 1 deletions

diff --git a/llvm/test/CodeGen/ARM/global-merge.ll b/llvm/test/CodeGen/ARM/global-merge.ll
index 1732df3fa5e..f88e9279619 100644
--- a/llvm/test/CodeGen/ARM/global-merge.ll
+++ b/llvm/test/CodeGen/ARM/global-merge.ll
@@ -1,4 +1,4 @@
-; RUN: llc < %s -mtriple=thumb-apple-darwin | FileCheck %s
+; RUN: llc < %s -mtriple=thumb-apple-darwin -global-merge-on-const=true | FileCheck %s
 ; Test the ARMGlobalMerge pass.  Use -march=thumb because it has a small
 ; value for the maximum offset (127).
 
@@ -6,6 +6,52 @@
 ; CHECK: g0:
 @g0 = internal global [32 x i32] [ i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 1, i32 2 ]
 
+; Global variables marked with "used" attribute must be kept
+; CHECK: g8
+@g8 = internal global i32 0
+@llvm.used = appending global [1 x i8*] [i8* bitcast (i32* @g8 to i8*)], section "llvm.metadata"
+
+; Global used in landing pad instruction must be kept
+; CHECK: ZTIi
+@_ZTIi = internal global i8* null
+
+define i32 @_Z9exceptioni(i32 %arg) {
+bb:
+  %tmp = invoke i32 @_Z14throwSomethingi(i32 %arg)
+          to label %bb9 unwind label %bb1
+
+bb1:                                              ; preds = %bb
+  %tmp2 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_sj0 to i8*)
+          catch i8* bitcast (i8** @_ZTIi to i8*)
+  %tmp3 = extractvalue { i8*, i32 } %tmp2, 1
+  %tmp4 = tail call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*))
+  %tmp5 = icmp eq i32 %tmp3, %tmp4
+  br i1 %tmp5, label %bb6, label %bb10
+
+bb6:                                              ; preds = %bb1
+  %tmp7 = extractvalue { i8*, i32 } %tmp2, 0
+  %tmp8 = tail call i8* @__cxa_begin_catch(i8* %tmp7)
+  tail call void @__cxa_end_catch()
+  br label %bb9
+
+bb9:                                              ; preds = %bb6, %bb
+  %res.0 = phi i32 [ 0, %bb6 ], [ %tmp, %bb ]
+  ret i32 %res.0
+
+bb10:                                             ; preds = %bb1
+  resume { i8*, i32 } %tmp2
+}
+
+declare i32 @_Z14throwSomethingi(i32)
+
+declare i32 @__gxx_personality_sj0(...)
+
+declare i32 @llvm.eh.typeid.for(i8*)
+
+declare i8* @__cxa_begin_catch(i8*)
+
+declare void @__cxa_end_catch()
+
 ; CHECK: _MergedGlobals:
 @g1 = internal global i32 1
 @g2 = internal global i32 2
@@ -21,3 +67,8 @@
 ; CHECK: _MergedGlobals2
 @g4 = internal global i32 0
 @g5 = internal global i32 0
+
+; Global variables that are constant can be merged together
+; CHECK: _MergedGlobals3
+@g6 = internal constant [12 x i32] zeroinitializer, align 4
+@g7 = internal constant [12 x i32] zeroinitializer, align 4