Jason W Kim 93cb3f967d This fixes one divergence between LLVM and binutils for ARM in the ... text section. Assume the following bit of annotated assembly: .section .data.rel.ro,"aw",%progbits .align 2 .LAlpha: .long startval(GOTOFF) .text .align 2 .type main,%function .align 4 main: ;;; assume "main" starts at offset 0x20 0x0 push {r11, lr} 0x4 movw r0, :lower16:(.LAlpha-(.LBeta+8)) ;;; ==> (.AddrOf(.LAlpha) - ((.AddrOf(.LBeta) - .AddrOf(".")) + 8) ;;; ==> (??? - ((16-4) + 8) = -20 0x8 movt r0, :upper16:(.LAlpha-(.LBeta+8)) ;;; ==> (.AddrOf(.LAlpha) - ((.AddrOf(.LBeta) - .AddrOf(".")) + 8) ;;; ==> (??? - ((16-8) + 8) = -16 0xc ... blah .LBeta: 0x10 add r0, pc, r0 0x14 ... blah .LGamma: 0x18 add r1, pc, r1 Above snippet results in the following relocs in the .o file for the first pair of movw/movt instructions 00000024 R_ARM_MOVW_PREL_NC .LAlpha 00000028 R_ARM_MOVT_PREL .LAlpha And the encoded instructions in the .o file for main: must be 00000020 <main>: 20: e92d4800 push {fp, lr} 24: e30f0fec movw r0, #65516 ; 0xffec i.e. -20 28: e34f0ff0 movt r0, #65520 ; 0xfff0 i.e. -16 However, llc (prior to this commit) generates the following sequence 00000020 <main>: 20: e92d4800 push {fp, lr} 24: e30f0fec movw r0, #65516 ; 0xffec - i.e. -20 28: e34f0fff movt r0, #65535 ; 0xffff - i.e. -1 What has to happen in the ArmAsmBackend is that if the relocation is PC relative, the 16 bits encoded as part of movw and movt must be both addends, not addresses. It makes sense to encode addresses by right shifting the value by 16, but the result is incorrect for PIC. i.e., the right shift by 16 for movt is ONLY valid for the NON-PCRel case. This change agrees with what GNU as does, and makes the PIC code run. MC/ARM/elf-movt.s covers this case. llvm-svn: 131674		2011-05-19 20:55:25 +00:00
..
Analysis	@llvm.lifetime.begin acts as a load, not @llvm.lifetime.end.	2011-05-17 00:05:49 +00:00
Archive	Revert PathV2 changes, as sys::fs::unique_file is not finished yet.	2011-03-01 19:50:55 +00:00
AsmParser	Remove unused variables caught by GCC's -Wunused-but-set-variable.	2011-05-03 16:00:27 +00:00
Bitcode	It's valid to take the blockaddress of a different function, so remove this	2011-05-06 21:09:44 +00:00
CodeGen	Update some currently-disabled code, preparing for eventual use.	2011-05-19 18:48:20 +00:00
CompilerDriver	Build CompilerDriver library.	2011-03-12 22:01:42 +00:00
ExecutionEngine	Avoid a Twine that referenced a tmp (which proceded to go out of scope before	2011-05-19 00:45:05 +00:00
Linker	Set the unnamed_addr only when we're creating a new GV in the dest module.	2011-03-29 23:31:06 +00:00
MC	Implement the Win64 EH prolog instruction methods on the base MCStreamer.	2011-05-19 19:35:55 +00:00
Object	Remove dead variable pointed out by GCC 4.6 warnings, and reflow this a little	2011-05-02 05:05:29 +00:00
Support	Revert my previous patch. The cmake build had already been fixed.	2011-05-19 00:02:45 +00:00
Target	This fixes one divergence between LLVM and binutils for ARM in the	2011-05-19 20:55:25 +00:00
Transforms	Reapply r131605. This time with a fix, which is to use NoFolder.	2011-05-19 20:52:46 +00:00
VMCore	Shuffle StandardPasses.cpp into VMCore; add it to CMake.	2011-05-18 23:51:11 +00:00
CMakeLists.txt	Build CompilerDriver library.	2011-03-12 22:01:42 +00:00
Makefile	Add LLVMObject Library.	2010-11-15 03:21:41 +00:00