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* [ARM] Make InstrEmitter mark CPSR defs dead for Thumb1.Eli Friedman2018-10-261-2/+7
| | | | | | | | | | | | | | | | | | The "dead" markings allow existing target-independent optimizations, like MachineSink, to trigger more frequently. The CPSR defs would have eventually been marked dead by LiveVariables, so this only affects optimizations before regalloc. The ARMBaseInstrInfo.cpp change is fixing a bug which is only visible with this change: the transform adds a use to an otherwise dead def of CPSR. This is covered by existing regression tests. thumb2-tbh.ll breaks for Thumb1 due to MachineLICM changing the generated code; I'll fix it in D53452. Differential Revision: https://reviews.llvm.org/D53453 llvm-svn: 345420
* [Thumb-1] Synthesize TBB/TBH instructions to make use of compressed jump tablesJames Molloy2016-11-011-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | [Reapplying r284580 and r285917 with fix and testing to ensure emitted jump tables for Thumb-1 have 4-byte alignment] The TBB and TBH instructions in Thumb-2 allow jump tables to be compressed into sequences of bytes or shorts respectively. These instructions do not exist in Thumb-1, however it is possible to synthesize them out of a sequence of other instructions. It turns out this sequence is so short that it's almost never a lose for performance and is ALWAYS a significant win for code size. TBB example: Before: lsls r0, r0, #2 After: add r0, pc adr r1, .LJTI0_0 ldrb r0, [r0, #6] ldr r0, [r0, r1] lsls r0, r0, #1 mov pc, r0 add pc, r0 => No change in prologue code size or dynamic instruction count. Jump table shrunk by a factor of 4. The only case that can increase dynamic instruction count is the TBH case: Before: lsls r0, r4, #2 After: lsls r4, r4, #1 adr r1, .LJTI0_0 add r4, pc ldr r0, [r0, r1] ldrh r4, [r4, #6] mov pc, r0 lsls r4, r4, #1 add pc, r4 => 1 more instruction in prologue. Jump table shrunk by a factor of 2. So there is an argument that this should be disabled when optimizing for performance (and a TBH needs to be generated). I'm not so sure about that in practice, because on small cores with Thumb-1 performance is often tied to code size. But I'm willing to turn it off when optimizing for performance if people want (also note that TBHs are fairly rare in practice!) llvm-svn: 285690
* Revert r284580+r284917. ("Synthesize TBB/TBH instructions")Eli Friedman2016-10-241-6/+2
| | | | | | | The optimization has correctness issues, so reverting for now to fix tests on thumb1 targets. llvm-svn: 284993
* [Thumb-1] Synthesize TBB/TBH instructions to make use of compressed jump tablesJames Molloy2016-10-191-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | The TBB and TBH instructions in Thumb-2 allow jump tables to be compressed into sequences of bytes or shorts respectively. These instructions do not exist in Thumb-1, however it is possible to synthesize them out of a sequence of other instructions. It turns out this sequence is so short that it's almost never a lose for performance and is ALWAYS a significant win for code size. TBB example: Before: lsls r0, r0, #2 After: add r0, pc adr r1, .LJTI0_0 ldrb r0, [r0, #6] ldr r0, [r0, r1] lsls r0, r0, #1 mov pc, r0 add pc, r0 => No change in prologue code size or dynamic instruction count. Jump table shrunk by a factor of 4. The only case that can increase dynamic instruction count is the TBH case: Before: lsls r0, r4, #2 After: lsls r4, r4, #1 adr r1, .LJTI0_0 add r4, pc ldr r0, [r0, r1] ldrh r4, [r4, #6] mov pc, r0 lsls r4, r4, #1 add pc, r4 => 1 more instruction in prologue. Jump table shrunk by a factor of 2. So there is an argument that this should be disabled when optimizing for performance (and a TBH needs to be generated). I'm not so sure about that in practice, because on small cores with Thumb-1 performance is often tied to code size. But I'm willing to turn it off when optimizing for performance if people want (also note that TBHs are fairly rare in practice!) llvm-svn: 284580
* ARM: recommit r237590: allow jump tables to be placed as constant islands.Tim Northover2015-05-311-1/+11
| | | | | | | | | | | | | | | The original version didn't properly account for the base register being modified before the final jump, so caused miscompilations in Chromium and LLVM. I've fixed this and tested with an LLVM self-host (I don't have the means to build & test Chromium). The general idea remains the same: in pathological cases jump tables can be too far away from the instructions referencing them (like other constants) so they need to be movable. Should fix PR23627. llvm-svn: 238680
* Revert r237590, "ARM: allow jump tables to be placed as constant islands."Peter Collingbourne2015-05-211-11/+1
| | | | | | | Caused a miscompile of the Android port of Chromium, details forthcoming. llvm-svn: 237972
* ARM: allow jump tables to be placed as constant islands.Tim Northover2015-05-181-1/+11
| | | | | | | | | | | | | | | | | Previously, they were forced to immediately follow the actual branch instruction. This was usually OK (the LEAs actually accessing them got emitted nearby, and weren't usually separated much afterwards). Unfortunately, a sufficiently nasty phi elimination dumps many instructions right before the basic block terminator, and this can increase the range too much. This patch frees them up to be placed as usual by the constant islands pass, and consequently has to slightly modify the form of TBB/TBH tables to refer to a PC-relative label at the final jump. The other jump table formats were already position-independent. rdar://20813304 llvm-svn: 237590
* [opaque pointer type] Add textual IR support for explicit type parameter to ↵David Blaikie2015-03-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gep operator Similar to gep (r230786) and load (r230794) changes. Similar migration script can be used to update test cases, which successfully migrated all of LLVM and Polly, but about 4 test cases needed manually changes in Clang. (this script will read the contents of stdin and massage it into stdout - wrap it in the 'apply.sh' script shown in previous commits + xargs to apply it over a large set of test cases) import fileinput import sys import re rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL) def conv(match): line = match.group(1) line += match.group(4) line += ", " line += match.group(2) return line line = sys.stdin.read() off = 0 for match in re.finditer(rep, line): sys.stdout.write(line[off:match.start()]) sys.stdout.write(conv(match)) off = match.end() sys.stdout.write(line[off:]) llvm-svn: 232184
* [opaque pointer type] Add textual IR support for explicit type parameter to ↵David Blaikie2015-02-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | load instruction Essentially the same as the GEP change in r230786. A similar migration script can be used to update test cases, though a few more test case improvements/changes were required this time around: (r229269-r229278) import fileinput import sys import re pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)") for line in sys.stdin: sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line)) Reviewers: rafael, dexonsmith, grosser Differential Revision: http://reviews.llvm.org/D7649 llvm-svn: 230794
* Mass update to CodeGen tests to use CHECK-LABEL for labels corresponding to ↵Stephen Lin2013-07-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | function definitions for more informative error messages. No functionality change and all updated tests passed locally. This update was done with the following bash script: find test/CodeGen -name "*.ll" | \ while read NAME; do echo "$NAME" if ! grep -q "^; *RUN: *llc.*debug" $NAME; then TEMP=`mktemp -t temp` cp $NAME $TEMP sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \ while read FUNC; do sed -i '' "s/;\(.*\)\([A-Za-z0-9_-]*\):\( *\)$FUNC: *\$/;\1\2-LABEL:\3$FUNC:/g" $TEMP done sed -i '' "s/;\(.*\)-LABEL-LABEL:/;\1-LABEL:/" $TEMP sed -i '' "s/;\(.*\)-NEXT-LABEL:/;\1-NEXT:/" $TEMP sed -i '' "s/;\(.*\)-NOT-LABEL:/;\1-NOT:/" $TEMP sed -i '' "s/;\(.*\)-DAG-LABEL:/;\1-DAG:/" $TEMP mv $TEMP $NAME fi done llvm-svn: 186280
* Remove arm_apcscc from the test files. It is the default and doing thisRafael Espindola2010-06-171-13/+13
| | | | | | matches what llvm-gcc and clang now produce. llvm-svn: 106221
* Enable arm jumpt table adjustment.Jim Grosbach2009-11-171-1/+0
| | | | llvm-svn: 89143
* tbb opt off by defaultJim Grosbach2009-11-161-0/+1
| | | | llvm-svn: 88921
* remove xfailJim Grosbach2009-11-141-2/+0
| | | | llvm-svn: 88817
* Clean up testcase a bit. Simplify case blocks and adjust switch instruction ↵Jim Grosbach2009-11-121-7/+3
| | | | | | to not take an undefined value as input. llvm-svn: 86997
* Eliminate more uses of llvm-as and llvm-dis.Dan Gohman2009-09-091-1/+1
| | | | llvm-svn: 81293
* tbb / tbh instructions only branch forward, not backwards.Evan Cheng2009-07-291-0/+4
| | | | llvm-svn: 77522
* Optimize Thumb2 jumptable to use tbb / tbh when all the offsets fit in byte ↵Evan Cheng2009-07-291-0/+86
/ halfword. llvm-svn: 77422
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