[llvm-commits] [llvm] r143459 - in /llvm/trunk: lib/Target/XCore/XCoreISelDAGToDAG.cpp test/CodeGen/XCore/global_negative_offset.ll

[Richard Osborne]

Author: friedgold
Date: Tue Nov  1 06:31:53 2011
New Revision: 143459

URL: http://llvm.org/viewvc/llvm-project?rev=143459&view=rev
Log:
Don't fold negative offsets into cp / dp accesses to avoid relocation errors.
This can happen if the address + addend is less than the start of the cp / dp.

Added:
    llvm/trunk/test/CodeGen/XCore/global_negative_offset.ll
Modified:
    llvm/trunk/lib/Target/XCore/XCoreISelDAGToDAG.cpp

Modified: llvm/trunk/lib/Target/XCore/XCoreISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/XCore/XCoreISelDAGToDAG.cpp?rev=143459&r1=143458&r2=143459&view=diff
==============================================================================
--- llvm/trunk/lib/Target/XCore/XCoreISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/XCore/XCoreISelDAGToDAG.cpp Tue Nov  1 06:31:53 2011
@@ -120,7 +120,7 @@
     ConstantSDNode *CN = 0;
     if ((Addr.getOperand(0).getOpcode() == XCoreISD::DPRelativeWrapper)
       && (CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))
-      && (CN->getSExtValue() % 4 == 0)) {
+      && (CN->getSExtValue() % 4 == 0 && CN->getSExtValue() >= 0)) {
       // Constant word offset from a object in the data region
       Base = Addr.getOperand(0).getOperand(0);
       Offset = CurDAG->getTargetConstant(CN->getSExtValue(), MVT::i32);
@@ -141,7 +141,7 @@
     ConstantSDNode *CN = 0;
     if ((Addr.getOperand(0).getOpcode() == XCoreISD::CPRelativeWrapper)
       && (CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))
-      && (CN->getSExtValue() % 4 == 0)) {
+      && (CN->getSExtValue() % 4 == 0 && CN->getSExtValue() >= 0)) {
       // Constant word offset from a object in the data region
       Base = Addr.getOperand(0).getOperand(0);
       Offset = CurDAG->getTargetConstant(CN->getSExtValue(), MVT::i32);

Added: llvm/trunk/test/CodeGen/XCore/global_negative_offset.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/XCore/global_negative_offset.ll?rev=143459&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/XCore/global_negative_offset.ll (added)
+++ llvm/trunk/test/CodeGen/XCore/global_negative_offset.ll Tue Nov  1 06:31:53 2011
@@ -0,0 +1,25 @@
+; RUN: llc < %s -march=xcore | FileCheck %s
+
+; Don't fold negative offsets into cp / dp accesses to avoid a relocation
+; error if the address + addend is less than the start of the cp / dp.
+
+ at a = external constant [0 x i32], section ".cp.rodata"
+ at b = external global [0 x i32]
+
+define i32 *@f() nounwind {
+entry:
+; CHECK: f:
+; CHECK: ldaw r11, cp[a]
+; CHECK: sub r0, r11, 4
+	%0 = getelementptr [0 x i32]* @a, i32 0, i32 -1
+	ret i32* %0
+}
+
+define i32 *@g() nounwind {
+entry:
+; CHECK: g:
+; CHECK: ldaw [[REG:r[0-9]+]], dp[b]
+; CHECK: sub r0, [[REG]], 4
+	%0 = getelementptr [0 x i32]* @b, i32 0, i32 -1
+	ret i32* %0
+}