recommit r172363 & r171325 (reverted in r172756)

This adds minimalistic support for PHI nodes to llvm.objectsize() evaluation

fingers crossed so that it does break clang boostrap again..

llvm-svn: 176408

1 files changed, 128 insertions, 0 deletions

diff --git a/llvm/test/Transforms/InstCombine/objsize.ll b/llvm/test/Transforms/InstCombine/objsize.ll
index 31a3cb46e45..0ead9d12374 100644
--- a/llvm/test/Transforms/InstCombine/objsize.ll
+++ b/llvm/test/Transforms/InstCombine/objsize.ll
@@ -256,3 +256,131 @@ xpto:
 return:
   ret i32 7
 }
+
+declare noalias i8* @valloc(i32) nounwind
+
+; CHECK: @test14
+; CHECK: ret i32 6
+define i32 @test14(i32 %a) nounwind {
+  switch i32 %a, label %sw.default [
+    i32 1, label %sw.bb
+    i32 2, label %sw.bb1
+  ]
+
+sw.bb:
+  %call = tail call noalias i8* @malloc(i32 6) nounwind
+  br label %sw.epilog
+
+sw.bb1:
+  %call2 = tail call noalias i8* @calloc(i32 3, i32 2) nounwind
+  br label %sw.epilog
+
+sw.default:
+  %call3 = tail call noalias i8* @valloc(i32 6) nounwind
+  br label %sw.epilog
+
+sw.epilog:
+  %b.0 = phi i8* [ %call3, %sw.default ], [ %call2, %sw.bb1 ], [ %call, %sw.bb ]
+  %1 = tail call i32 @llvm.objectsize.i32(i8* %b.0, i1 false)
+  ret i32 %1
+}
+
+; CHECK: @test15
+; CHECK: llvm.objectsize
+define i32 @test15(i32 %a) nounwind {
+  switch i32 %a, label %sw.default [
+    i32 1, label %sw.bb
+    i32 2, label %sw.bb1
+  ]
+
+sw.bb:
+  %call = tail call noalias i8* @malloc(i32 3) nounwind
+  br label %sw.epilog
+
+sw.bb1:
+  %call2 = tail call noalias i8* @calloc(i32 2, i32 1) nounwind
+  br label %sw.epilog
+
+sw.default:
+  %call3 = tail call noalias i8* @valloc(i32 3) nounwind
+  br label %sw.epilog
+
+sw.epilog:
+  %b.0 = phi i8* [ %call3, %sw.default ], [ %call2, %sw.bb1 ], [ %call, %sw.bb ]
+  %1 = tail call i32 @llvm.objectsize.i32(i8* %b.0, i1 false)
+  ret i32 %1
+}
+
+; CHECK: @test16
+; CHECK: llvm.objectsize
+define i32 @test16(i8* %a, i32 %n) nounwind {
+  %b = alloca [5 x i8], align 1
+  %c = alloca [5 x i8], align 1
+  switch i32 %n, label %sw.default [
+    i32 1, label %sw.bb
+    i32 2, label %sw.bb1
+  ]
+
+sw.bb:
+  %bp = bitcast [5 x i8]* %b to i8*
+  br label %sw.epilog
+
+sw.bb1:
+  %cp = bitcast [5 x i8]* %c to i8*
+  br label %sw.epilog
+
+sw.default:
+  br label %sw.epilog
+
+sw.epilog:
+  %phi = phi i8* [ %a, %sw.default ], [ %cp, %sw.bb1 ], [ %bp, %sw.bb ]
+  %sz = call i32 @llvm.objectsize.i32(i8* %phi, i1 false)
+  ret i32 %sz
+}
+
+; CHECK: @test17
+; CHECK: ret i32 5
+define i32 @test17(i32 %n) nounwind {
+  %b = alloca [5 x i8], align 1
+  %c = alloca [5 x i8], align 1
+  %bp = bitcast [5 x i8]* %b to i8*
+  switch i32 %n, label %sw.default [
+    i32 1, label %sw.bb
+    i32 2, label %sw.bb1
+  ]
+
+sw.bb:
+  br label %sw.epilog
+
+sw.bb1:
+  %cp = bitcast [5 x i8]* %c to i8*
+  br label %sw.epilog
+
+sw.default:
+  br label %sw.epilog
+
+sw.epilog:
+  %phi = phi i8* [ %bp, %sw.default ], [ %cp, %sw.bb1 ], [ %bp, %sw.bb ]
+  %sz = call i32 @llvm.objectsize.i32(i8* %phi, i1 false)
+  ret i32 %sz
+}
+
+@globalalias = alias internal [60 x i8]* @a
+
+; CHECK: @test18
+; CHECK-NEXT: ret i32 60
+define i32 @test18() {
+  %bc = bitcast [60 x i8]* @globalalias to i8*
+  %1 = call i32 @llvm.objectsize.i32(i8* %bc, i1 false)
+  ret i32 %1
+}
+
+@globalalias2 = alias weak [60 x i8]* @a
+
+; CHECK: @test19
+; CHECK: llvm.objectsize
+define i32 @test19() {
+  %bc = bitcast [60 x i8]* @globalalias2 to i8*
+  %1 = call i32 @llvm.objectsize.i32(i8* %bc, i1 false)
+  ret i32 %1
+}