[MC][ARM] Correct Thumb BL instruction range

The Thumb BL range is + or - either 16 Megabytes or 4 Megabytes depending
on whether the CPU supports Thumb2 or the v8-m baseline ops. The existing
check for BL range is incorrectly set at +- 32 Megabytes. This change
corrects the higher range and uses the lower range if the featurebits
don't have the necessary support for it.

Differential Revision: https://reviews.llvm.org/D46305

llvm-svn: 333991

1 files changed, 5 insertions, 3 deletions

diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
index 40278629a01..8df49903ffe 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
@@ -518,9 +518,11 @@ unsigned ARMAsmBackend::adjustFixupValue(const MCAssembler &Asm,
     return swapHalfWords(out, Endian == support::little);
   }
   case ARM::fixup_arm_thumb_bl: {
-    // FIXME: We get both thumb1 and thumb2 in here, so we can only check for
-    // the less strict thumb2 value.
-    if (!isInt<26>(Value - 4)) {
+    if (!isInt<25>(Value - 4) ||
+        (!STI.getFeatureBits()[ARM::FeatureThumb2] &&
+         !STI.getFeatureBits()[ARM::HasV8MBaselineOps] &&
+         !STI.getFeatureBits()[ARM::HasV6MOps] &&
+         !isInt<23>(Value - 4))) {
       Ctx.reportError(Fixup.getLoc(), "Relocation out of range");
       return 0;
     }