Index: llvm/trunk/lib/Target/X86/X86AvoidStoreForwardingBlocks.cpp
===================================================================
--- llvm/trunk/lib/Target/X86/X86AvoidStoreForwardingBlocks.cpp
+++ llvm/trunk/lib/Target/X86/X86AvoidStoreForwardingBlocks.cpp
@@ -586,7 +586,7 @@
       StDisp2 += OverlapDelta;
       Size2 -= OverlapDelta;
     }
-    Size1 = std::abs(std::abs(LdDisp2) - std::abs(LdDisp1));
+    Size1 = LdDisp2 - LdDisp1;
 
     // Build a copy for the point until the current blocking store's
     // displacement.
Index: llvm/trunk/test/CodeGen/X86/pr39926.ll
===================================================================
--- llvm/trunk/test/CodeGen/X86/pr39926.ll
+++ llvm/trunk/test/CodeGen/X86/pr39926.ll
@@ -8,9 +8,9 @@
 ; CHECK-NEXT:    movb $0, 7(%rdi)
 ; CHECK-NEXT:    movw $0, 5(%rdi)
 ; CHECK-NEXT:    movl $0, 1(%rdi)
-; CHECK-NEXT:    movzwl -4(%rdi), %eax
-; CHECK-NEXT:    movw %ax, -{{[0-9]+}}(%rsp)
-; CHECK-NEXT:    movb -2(%rdi), %al
+; CHECK-NEXT:    movl -4(%rdi), %eax
+; CHECK-NEXT:    movl %eax, -{{[0-9]+}}(%rsp)
+; CHECK-NEXT:    movb (%rdi), %al
 ; CHECK-NEXT:    movb %al, -{{[0-9]+}}(%rsp)
 ; CHECK-NEXT:    movl 1(%rdi), %eax
 ; CHECK-NEXT:    movl %eax, -{{[0-9]+}}(%rsp)