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llvm-project/llvm/test/CodeGen/ARM/ifcvt10.ll

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ARM & AArch64: make use of common cmpxchg idioms after expansion The C and C++ semantics for compare_exchange require it to return a bool indicating success. This gets mapped to LLVM IR which follows each cmpxchg with an icmp of the value loaded against the desired value. When lowered to ldxr/stxr loops, this extra comparison is redundant: its results are implicit in the control-flow of the function. This commit makes two changes: it replaces that icmp with appropriate PHI nodes, and then makes sure earlyCSE is called after expansion to actually make use of the opportunities revealed. I've also added -{arm,aarch64}-enable-atomic-tidy options, so that existing fragile tests aren't perturbed too much by the change. Many of them either rely on undef/unreachable too pervasively to be restored to something well-defined (particularly while making sure they test the same obscure assert from many years ago), or depend on a particular CFG shape, which is disrupted by SimplifyCFG. rdar://problem/16227836 llvm-svn: 209883
2014-05-30 18:09:59 +08:00
; RUN: llc < %s -mtriple=arm-apple-ios -arm-atomic-cfg-tidy=0 -mcpu=cortex-a9 | FileCheck %s
Teach if-converter to be more careful with predicating instructions that would take multiple cycles to decode. For the current if-converter clients (actually only ARM), the instructions that are predicated on false are not nops. They would still take machine cycles to decode. Micro-coded instructions such as LDM / STM can potentially take multiple cycles to decode. If-converter should take treat them as non-micro-coded simple instructions. llvm-svn: 113570
2010-09-10 09:29:16 +08:00
; rdar://8402126
; Make sure if-converter is not predicating vldmia and ldmia. These are
; micro-coded and would have long issue latency even if predicated on
; false predicate.
[ARM] Generate consistent frame records for Thumb2 There is not an official documented ABI for frame pointers in Thumb2, but we should try to emit something which is useful. We use r7 as the frame pointer for Thumb code, which currently means that if a function needs to save a high register (r8-r11), it will get pushed to the stack between the frame pointer (r7) and link register (r14). This means that while a stack unwinder can follow the chain of frame pointers up the stack, it cannot know the offset to lr, so does not know which functions correspond to the stack frames. To fix this, we need to push the callee-saved registers in two batches, with the first push saving the low registers, fp and lr, and the second push saving the high registers. This is already implemented, but previously only used for iOS. This patch turns it on for all Thumb2 targets when frame pointers are required by the ABI, and the frame pointer is r7 (Windows uses r11, so this isn't a problem there). If frame pointer elimination is enabled we still emit a single push/pop even if we need a frame pointer for other reasons, to avoid increasing code size. We must also ensure that lr is pushed to the stack when using a frame pointer, so that we end up with a complete frame record. Situations that could cause this were rare, because we already push lr in most situations so that we can return using the pop instruction. Differential Revision: https://reviews.llvm.org/D23516 llvm-svn: 279506
2016-08-23 17:19:22 +08:00
define void @t(double %a, double %b, double %c, double %d, i32* nocapture %solutions, double* nocapture %x) nounwind "no-frame-pointer-elim"="true" {
Teach if-converter to be more careful with predicating instructions that would take multiple cycles to decode. For the current if-converter clients (actually only ARM), the instructions that are predicated on false are not nops. They would still take machine cycles to decode. Micro-coded instructions such as LDM / STM can potentially take multiple cycles to decode. If-converter should take treat them as non-micro-coded simple instructions. llvm-svn: 113570
2010-09-10 09:29:16 +08:00
entry:
Mass update to CodeGen tests to use CHECK-LABEL for labels corresponding to 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
2013-07-14 14:24:09 +08:00
; CHECK-LABEL: t:
Two sets of changes. Sorry they are intermingled. 1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to "optimize for latency". Call instructions don't have the right latency and this is more likely to use introduce spills. 2. Fix if-converter cost function. For ARM, it should use instruction latencies, not # of micro-ops since multi-latency instructions is completely executed even when the predicate is false. Also, some instruction will be "slower" when they are predicated due to the register def becoming implicit input. rdar://8598427 llvm-svn: 118135
2010-11-03 08:45:17 +08:00
; CHECK: vpop {d8}
; CHECK-NOT: vpopne
[SDAG] Revert r296476 (and r296486, r296668, r296690). This patch causes compile times for some patterns to explode. I have a (large, unreduced) test case that slows down by more than 20x and several test cases slow down by 2x. I'm sending some of the test cases directly to Nirav and following up with more details in the review log, but this should unblock anyone else hitting this. llvm-svn: 296862
2017-03-03 18:02:25 +08:00
; CHECK: pop {r7, pc}
; CHECK: vpop {d8}
Properly pseudo-ize the ARM LDMIA_RET instruction. This has the nice side- effect that we get proper instruction printing using the "pop" mnemonic for it. llvm-svn: 127502
2011-03-12 06:51:41 +08:00
; CHECK: pop {r7, pc}
Two sets of changes. Sorry they are intermingled. 1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to "optimize for latency". Call instructions don't have the right latency and this is more likely to use introduce spills. 2. Fix if-converter cost function. For ARM, it should use instruction latencies, not # of micro-ops since multi-latency instructions is completely executed even when the predicate is false. Also, some instruction will be "slower" when they are predicated due to the register def becoming implicit input. rdar://8598427 llvm-svn: 118135
2010-11-03 08:45:17 +08:00
br i1 undef, label %if.else, label %if.then
Teach if-converter to be more careful with predicating instructions that would take multiple cycles to decode. For the current if-converter clients (actually only ARM), the instructions that are predicated on false are not nops. They would still take machine cycles to decode. Micro-coded instructions such as LDM / STM can potentially take multiple cycles to decode. If-converter should take treat them as non-micro-coded simple instructions. llvm-svn: 113570
2010-09-10 09:29:16 +08:00
Two sets of changes. Sorry they are intermingled. 1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to "optimize for latency". Call instructions don't have the right latency and this is more likely to use introduce spills. 2. Fix if-converter cost function. For ARM, it should use instruction latencies, not # of micro-ops since multi-latency instructions is completely executed even when the predicate is false. Also, some instruction will be "slower" when they are predicated due to the register def becoming implicit input. rdar://8598427 llvm-svn: 118135
2010-11-03 08:45:17 +08:00
if.then: ; preds = %entry
%mul73 = fmul double undef, 0.000000e+00
%sub76 = fsub double %mul73, undef
store double %sub76, double* undef, align 4
%call88 = tail call double @cos(double 0.000000e+00) nounwind
%mul89 = fmul double undef, %call88
%sub92 = fsub double %mul89, undef
store double %sub92, double* undef, align 4
ret void
Teach if-converter to be more careful with predicating instructions that would take multiple cycles to decode. For the current if-converter clients (actually only ARM), the instructions that are predicated on false are not nops. They would still take machine cycles to decode. Micro-coded instructions such as LDM / STM can potentially take multiple cycles to decode. If-converter should take treat them as non-micro-coded simple instructions. llvm-svn: 113570
2010-09-10 09:29:16 +08:00
Two sets of changes. Sorry they are intermingled. 1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to "optimize for latency". Call instructions don't have the right latency and this is more likely to use introduce spills. 2. Fix if-converter cost function. For ARM, it should use instruction latencies, not # of micro-ops since multi-latency instructions is completely executed even when the predicate is false. Also, some instruction will be "slower" when they are predicated due to the register def becoming implicit input. rdar://8598427 llvm-svn: 118135
2010-11-03 08:45:17 +08:00
if.else: ; preds = %entry
%tmp101 = tail call double @llvm.pow.f64(double undef, double 0x3FD5555555555555)
%add112 = fadd double %tmp101, undef
%mul118 = fmul double %add112, undef
store double 0.000000e+00, double* %x, align 4
ret void
Teach if-converter to be more careful with predicating instructions that would take multiple cycles to decode. For the current if-converter clients (actually only ARM), the instructions that are predicated on false are not nops. They would still take machine cycles to decode. Micro-coded instructions such as LDM / STM can potentially take multiple cycles to decode. If-converter should take treat them as non-micro-coded simple instructions. llvm-svn: 113570
2010-09-10 09:29:16 +08:00
}
Two sets of changes. Sorry they are intermingled. 1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to "optimize for latency". Call instructions don't have the right latency and this is more likely to use introduce spills. 2. Fix if-converter cost function. For ARM, it should use instruction latencies, not # of micro-ops since multi-latency instructions is completely executed even when the predicate is false. Also, some instruction will be "slower" when they are predicated due to the register def becoming implicit input. rdar://8598427 llvm-svn: 118135
2010-11-03 08:45:17 +08:00
declare double @acos(double)
declare double @sqrt(double) readnone
declare double @cos(double) readnone
declare double @fabs(double)
declare double @llvm.pow.f64(double, double) nounwind readonly