From: Jim Grosbach <grosbach@apple.com>
Date: Fri, 24 Jun 2011 20:06:59 +0000 (+0000)
Subject: ARM movw/movt fixups need to mask the high bits.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=8b45456700f1e156b0a14000124f274dfac86f14;p=oota-llvm.git

ARM movw/movt fixups need to mask the high bits.

The fixup value comes in as the whole 32-bit value, so for the lo16 fixup,
the upper bits need to be masked off. Previously we assumed the masking had
already been done and asserted.

rdar://9635991

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133818 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/ARM/ARMAsmBackend.cpp b/lib/Target/ARM/ARMAsmBackend.cpp
index 79e98970600..5e438a97673 100644
--- a/lib/Target/ARM/ARMAsmBackend.cpp
+++ b/lib/Target/ARM/ARMAsmBackend.cpp
@@ -174,7 +174,8 @@ static unsigned adjustFixupValue(unsigned Kind, uint64_t Value) {
     Value >>= 16;
     // Fallthrough
   case ARM::fixup_t2_movw_lo16:
-  case ARM::fixup_t2_movt_hi16_pcrel:
+  case ARM::fixup_t2_movt_hi16_pcrel:  //FIXME: Shouldn't this be shifted like
+                                       // the other hi16 fixup?
   case ARM::fixup_t2_movw_lo16_pcrel: {
     unsigned Hi4 = (Value & 0xF000) >> 12;
     unsigned i = (Value & 0x800) >> 11;
@@ -184,8 +185,10 @@ static unsigned adjustFixupValue(unsigned Kind, uint64_t Value) {
     // inst{26} = i;
     // inst{14-12} = Mid3;
     // inst{7-0} = Lo8;
-    assert ((((int64_t)Value) >= -0x8000) && (((int64_t)Value) <= 0x7fff) &&
-            "Out of range pc-relative fixup value!");
+    // The value comes in as the whole thing, not just the portion required
+    // for this fixup, so we need to mask off the bits not handled by this
+    // portion (lo vs. hi).
+    Value &= 0xffff;
     Value = (Hi4 << 16) | (i << 26) | (Mid3 << 12) | (Lo8);
     uint64_t swapped = (Value & 0xFFFF0000) >> 16;
     swapped |= (Value & 0x0000FFFF) << 16;