Fix <rdar://problem/9476260> by having tail calls always generate 32-bit branches

in Darwin Thumb2 code. Tail calls are already disabled on Thumb1.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131894 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/ARMAsmPrinter.cpp b/lib/Target/ARM/ARMAsmPrinter.cpp
index 15dc9bdcbfb9835d3425115b006987d77d7250d1..ff8f8a8a8e0f101498a3c2d7c1f679a0cebf2f0f 100644 (file)
--- a/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -1832,7 +1832,9 @@ void ARMAsmPrinter::EmitInstruction(const MachineInstr *MI) {
   case ARM::tTAILJMPdND: {
     MCInst TmpInst, TmpInst2;
     LowerARMMachineInstrToMCInst(MI, TmpInst2, *this);
-    TmpInst.setOpcode(ARM::tB);
+    // The Darwin toolchain doesn't support tail call relocations of 16-bit
+    // branches.
+    TmpInst.setOpcode(Opc == ARM::tTAILJMPd ? ARM::t2B : ARM::tB);
     TmpInst.addOperand(TmpInst2.getOperand(0));
     OutStreamer.AddComment("TAILCALL");
     OutStreamer.EmitInstruction(TmpInst);

diff --git a/test/CodeGen/ARM/call-tc.ll b/test/CodeGen/ARM/call-tc.ll
index 4dc37aa27558023f92883f2416692b463dbe73f5..2f3e02bea6b05f963c4c894065afc15230f39441 100644 (file)
--- a/test/CodeGen/ARM/call-tc.ll
+++ b/test/CodeGen/ARM/call-tc.ll
@@ -1,6 +1,6 @@
 ; RUN: llc < %s -mtriple=armv6-apple-darwin -mattr=+vfp2 -arm-tail-calls | FileCheck %s -check-prefix=CHECKV6
 ; RUN: llc < %s -mtriple=armv6-linux-gnueabi -relocation-model=pic -mattr=+vfp2 -arm-tail-calls | FileCheck %s -check-prefix=CHECKELF
-; RUN: llc < %s -mtriple=thumbv7-apple-darwin -arm-tail-calls | FileCheck %s -check-prefix=CHECKT2
+; RUN: llc < %s -mtriple=thumbv7-apple-darwin -arm-tail-calls | FileCheck %s -check-prefix=CHECKT2D
 
 @t = weak global i32 ()* null           ; <i32 ()**> [#uses=1]
 
@@ -26,6 +26,9 @@ define void @t3() {
 ; CHECKV6: b _t2  @ TAILCALL
 ; CHECKELF: t3:
 ; CHECKELF: b t2(PLT) @ TAILCALL
+; CHECKT2D: t3:
+; CHECKT2D: b.w _t2  @ TAILCALL
+
         tail call void @t2( )            ; <i32> [#uses=0]
         ret void
 }
@@ -71,10 +74,10 @@ declare void @foo() nounwind
 
 define void @t7() nounwind {
 entry:
-; CHECKT2: t7:
-; CHECKT2: blxeq _foo
-; CHECKT2-NEXT: pop.w
-; CHECKT2-NEXT: b _foo
+; CHECKT2D: t7:
+; CHECKT2D: blxeq _foo
+; CHECKT2D-NEXT: pop.w
+; CHECKT2D-NEXT: b.w _foo
   br i1 undef, label %bb, label %bb1.lr.ph
 
 bb1.lr.ph: