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path: root/lib/Target/ARM/README-Thumb2.txt
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* New entry.Evan Cheng2009-08-14
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78968 91177308-0d34-0410-b5e6-96231b3b80d8
* This is done.Evan Cheng2009-08-07
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78399 91177308-0d34-0410-b5e6-96231b3b80d8
* Use 16-bit tMOVgpr2gpr instead of tMOVr to copy GPR registers in Thumb2 mode.Evan Cheng2009-08-07
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78398 91177308-0d34-0410-b5e6-96231b3b80d8
* It turns out most of the thumb2 instructions are not allowed to touch SP. ↵Evan Cheng2009-08-07
| | | | | | | | | | | The semantics of such instructions are unpredictable. We have just been lucky that tests have been passing. This patch takes pain to ensure all the PEI lowering code does the right thing when lowering frame indices, insert code to manipulate stack pointers, etc. It's also custom lowering dynamic stack alloc into pseudo instructions so we can insert the right instructions at scheduling time. This fixes PR4659 and PR4682. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78361 91177308-0d34-0410-b5e6-96231b3b80d8
* These are done.Evan Cheng2009-08-03
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77949 91177308-0d34-0410-b5e6-96231b3b80d8
* Change Thumb2 jumptable codegen to one that uses two level jumps:Evan Cheng2009-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before: adr r12, #LJTI3_0_0 ldr pc, [r12, +r0, lsl #2] LJTI3_0_0: .long LBB3_24 .long LBB3_30 .long LBB3_31 .long LBB3_32 After: adr r12, #LJTI3_0_0 add pc, r12, +r0, lsl #2 LJTI3_0_0: b.w LBB3_24 b.w LBB3_30 b.w LBB3_31 b.w LBB3_32 This has several advantages. 1. This will make it easier to optimize this to a TBB / TBH instruction + (smaller) table. 2. This eliminate the need for ugly asm printer hack to force the address into thumb addresses (bit 0 is one). 3. Same codegen for pic and non-pic. 4. This eliminate the need to align the table so constantpool island pass won't have to over-estimate the size. Based on my calculation, the later is probably slightly faster as well since ldr pc with shifter address is very slow. That is, it should be a win as long as the HW implementation can do a reasonable job of branch predict the second branch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77024 91177308-0d34-0410-b5e6-96231b3b80d8
* Add a todo.Evan Cheng2009-07-08
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74976 91177308-0d34-0410-b5e6-96231b3b80d8