[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
|
2019-01-25 00:11:25 +01:00
|
|
|
# RUN: llc -O0 -march=aarch64 -run-pass=legalizer %s -o - | FileCheck %s
|
2016-08-26 19:46:13 +02:00
|
|
|
---
|
2017-08-30 21:32:59 +02:00
|
|
|
name: test_urem_64
|
2018-11-06 19:59:18 +01:00
|
|
|
body: |
|
2016-08-26 19:46:13 +02:00
|
|
|
bb.0.entry:
|
2017-08-30 21:32:59 +02:00
|
|
|
; CHECK-LABEL: name: test_urem_64
|
2018-01-31 23:04:26 +01:00
|
|
|
; CHECK: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
|
|
|
|
|
; CHECK: [[COPY1:%[0-9]+]]:_(s64) = COPY $x1
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[UDIV:%[0-9]+]]:_(s64) = G_UDIV [[COPY]], [[COPY1]]
|
|
|
|
|
; CHECK: [[MUL:%[0-9]+]]:_(s64) = G_MUL [[UDIV]], [[COPY1]]
|
|
|
|
|
; CHECK: [[SUB:%[0-9]+]]:_(s64) = G_SUB [[COPY]], [[MUL]]
|
2018-01-31 23:04:26 +01:00
|
|
|
; CHECK: $x0 = COPY [[SUB]](s64)
|
2018-11-06 19:59:18 +01:00
|
|
|
%0:_(s64) = COPY $x0
|
|
|
|
|
%1:_(s64) = COPY $x1
|
|
|
|
|
%2:_(s64) = G_UREM %0, %1
|
|
|
|
|
$x0 = COPY %2(s64)
|
2017-08-30 21:32:59 +02:00
|
|
|
|
|
|
|
|
...
|
|
|
|
|
---
|
|
|
|
|
name: test_srem_32
|
2018-11-06 19:59:18 +01:00
|
|
|
body: |
|
2017-08-30 21:32:59 +02:00
|
|
|
bb.0.entry:
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK-LABEL: name: test_srem_32
|
2018-01-31 23:04:26 +01:00
|
|
|
; CHECK: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
|
|
|
|
|
; CHECK: [[COPY1:%[0-9]+]]:_(s64) = COPY $x1
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[TRUNC:%[0-9]+]]:_(s32) = G_TRUNC [[COPY]](s64)
|
|
|
|
|
; CHECK: [[TRUNC1:%[0-9]+]]:_(s32) = G_TRUNC [[COPY1]](s64)
|
|
|
|
|
; CHECK: [[SDIV:%[0-9]+]]:_(s32) = G_SDIV [[TRUNC]], [[TRUNC1]]
|
|
|
|
|
; CHECK: [[MUL:%[0-9]+]]:_(s32) = G_MUL [[SDIV]], [[TRUNC1]]
|
|
|
|
|
; CHECK: [[SUB:%[0-9]+]]:_(s32) = G_SUB [[TRUNC]], [[MUL]]
|
2018-01-31 23:04:26 +01:00
|
|
|
; CHECK: $w0 = COPY [[SUB]](s32)
|
2018-11-06 19:59:18 +01:00
|
|
|
%0:_(s64) = COPY $x0
|
|
|
|
|
%1:_(s64) = COPY $x1
|
|
|
|
|
%2:_(s32) = G_TRUNC %0(s64)
|
|
|
|
|
%3:_(s32) = G_TRUNC %1(s64)
|
|
|
|
|
%4:_(s32) = G_SREM %2, %3
|
|
|
|
|
$w0 = COPY %4(s32)
|
2016-08-26 19:46:13 +02:00
|
|
|
|
2017-08-30 21:32:59 +02:00
|
|
|
...
|
|
|
|
|
---
|
|
|
|
|
name: test_srem_8
|
2018-11-06 19:59:18 +01:00
|
|
|
body: |
|
2017-08-30 21:32:59 +02:00
|
|
|
bb.0.entry:
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK-LABEL: name: test_srem_8
|
2018-01-31 23:04:26 +01:00
|
|
|
; CHECK: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
|
|
|
|
|
; CHECK: [[COPY1:%[0-9]+]]:_(s64) = COPY $x1
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[TRUNC:%[0-9]+]]:_(s32) = G_TRUNC [[COPY]](s64)
|
[globalisel] Add G_SEXT_INREG
Summary:
Targets often have instructions that can sign-extend certain cases faster
than the equivalent shift-left/arithmetic-shift-right. Such cases can be
identified by matching a shift-left/shift-right pair but there are some
issues with this in the context of combines. For example, suppose you can
sign-extend 8-bit up to 32-bit with a target extend instruction.
%1:_(s32) = G_SHL %0:_(s32), i32 24 # (I've inlined the G_CONSTANT for brevity)
%2:_(s32) = G_ASHR %1:_(s32), i32 24
%3:_(s32) = G_ASHR %2:_(s32), i32 1
would reasonably combine to:
%1:_(s32) = G_SHL %0:_(s32), i32 24
%2:_(s32) = G_ASHR %1:_(s32), i32 25
which no longer matches the special case. If your shifts and extend are
equal cost, this would break even as a pair of shifts but if your shift is
more expensive than the extend then it's cheaper as:
%2:_(s32) = G_SEXT_INREG %0:_(s32), i32 8
%3:_(s32) = G_ASHR %2:_(s32), i32 1
It's possible to match the shift-pair in ISel and emit an extend and ashr.
However, this is far from the only way to break this shift pair and make
it hard to match the extends. Another example is that with the right
known-zeros, this:
%1:_(s32) = G_SHL %0:_(s32), i32 24
%2:_(s32) = G_ASHR %1:_(s32), i32 24
%3:_(s32) = G_MUL %2:_(s32), i32 2
can become:
%1:_(s32) = G_SHL %0:_(s32), i32 24
%2:_(s32) = G_ASHR %1:_(s32), i32 23
All upstream targets have been configured to lower it to the current
G_SHL,G_ASHR pair but will likely want to make it legal in some cases to
handle their faster cases.
To follow-up: Provide a way to legalize based on the constant. At the
moment, I'm thinking that the best way to achieve this is to provide the
MI in LegalityQuery but that opens the door to breaking core principles
of the legalizer (legality is not context sensitive). That said, it's
worth noting that looking at other instructions and acting on that
information doesn't violate this principle in itself. It's only a
violation if, at the end of legalization, a pass that checks legality
without being able to see the context would say an instruction might not be
legal. That's a fairly subtle distinction so to give a concrete example,
saying %2 in:
%1 = G_CONSTANT 16
%2 = G_SEXT_INREG %0, %1
is legal is in violation of that principle if the legality of %2 depends
on %1 being constant and/or being 16. However, legalizing to either:
%2 = G_SEXT_INREG %0, 16
or:
%1 = G_CONSTANT 16
%2:_(s32) = G_SHL %0, %1
%3:_(s32) = G_ASHR %2, %1
depending on whether %1 is constant and 16 does not violate that principle
since both outputs are genuinely legal.
Reviewers: bogner, aditya_nandakumar, volkan, aemerson, paquette, arsenm
Subscribers: sdardis, jvesely, wdng, nhaehnle, rovka, kristof.beyls, javed.absar, hiraditya, jrtc27, atanasyan, Petar.Avramovic, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61289
llvm-svn: 368487
2019-08-09 23:11:20 +02:00
|
|
|
; CHECK: [[C:%[0-9]+]]:_(s32) = G_CONSTANT i32 24
|
2019-07-03 03:49:06 +02:00
|
|
|
; CHECK: [[SHL:%[0-9]+]]:_(s32) = G_SHL [[TRUNC]], [[C]](s32)
|
|
|
|
|
; CHECK: [[C1:%[0-9]+]]:_(s64) = G_CONSTANT i64 24
|
|
|
|
|
; CHECK: [[COPY2:%[0-9]+]]:_(s64) = COPY [[C1]](s64)
|
|
|
|
|
; CHECK: [[ASHR:%[0-9]+]]:_(s32) = G_ASHR [[SHL]], [[COPY2]](s64)
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[TRUNC1:%[0-9]+]]:_(s32) = G_TRUNC [[COPY1]](s64)
|
2019-07-03 03:49:06 +02:00
|
|
|
; CHECK: [[SHL1:%[0-9]+]]:_(s32) = G_SHL [[TRUNC1]], [[C]](s32)
|
|
|
|
|
; CHECK: [[ASHR1:%[0-9]+]]:_(s32) = G_ASHR [[SHL1]], [[C1]](s64)
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[SDIV:%[0-9]+]]:_(s32) = G_SDIV [[ASHR]], [[ASHR1]]
|
2019-07-03 03:49:06 +02:00
|
|
|
; CHECK: [[COPY3:%[0-9]+]]:_(s32) = COPY [[SDIV]](s32)
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[TRUNC2:%[0-9]+]]:_(s32) = G_TRUNC [[COPY1]](s64)
|
2019-07-03 03:49:06 +02:00
|
|
|
; CHECK: [[MUL:%[0-9]+]]:_(s32) = G_MUL [[COPY3]], [[TRUNC2]]
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[TRUNC3:%[0-9]+]]:_(s32) = G_TRUNC [[COPY]](s64)
|
2019-07-03 03:49:06 +02:00
|
|
|
; CHECK: [[COPY4:%[0-9]+]]:_(s32) = COPY [[MUL]](s32)
|
|
|
|
|
; CHECK: [[SUB:%[0-9]+]]:_(s32) = G_SUB [[TRUNC3]], [[COPY4]]
|
|
|
|
|
; CHECK: [[COPY5:%[0-9]+]]:_(s32) = COPY [[SUB]](s32)
|
|
|
|
|
; CHECK: $w0 = COPY [[COPY5]](s32)
|
2018-11-06 19:59:18 +01:00
|
|
|
%0:_(s64) = COPY $x0
|
|
|
|
|
%1:_(s64) = COPY $x1
|
|
|
|
|
%2:_(s8) = G_TRUNC %0(s64)
|
|
|
|
|
%3:_(s8) = G_TRUNC %1(s64)
|
|
|
|
|
%4:_(s8) = G_SREM %2, %3
|
|
|
|
|
%5:_(s32) = G_ANYEXT %4(s8)
|
|
|
|
|
$w0 = COPY %5(s32)
|
|
|
|
|
|
2017-08-30 21:32:59 +02:00
|
|
|
...
|
|
|
|
|
---
|
|
|
|
|
name: test_frem
|
2018-11-06 19:59:18 +01:00
|
|
|
body: |
|
2017-08-30 21:32:59 +02:00
|
|
|
bb.0.entry:
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK-LABEL: name: test_frem
|
2018-01-31 23:04:26 +01:00
|
|
|
; CHECK: [[COPY:%[0-9]+]]:_(s64) = COPY $x0
|
|
|
|
|
; CHECK: [[COPY1:%[0-9]+]]:_(s64) = COPY $x1
|
|
|
|
|
; CHECK: ADJCALLSTACKDOWN 0, 0, implicit-def $sp, implicit $sp
|
|
|
|
|
; CHECK: $d0 = COPY [[COPY]](s64)
|
|
|
|
|
; CHECK: $d1 = COPY [[COPY1]](s64)
|
|
|
|
|
; CHECK: BL &fmod, csr_aarch64_aapcs, implicit-def $lr, implicit $sp, implicit $d0, implicit $d1, implicit-def $d0
|
|
|
|
|
; CHECK: [[COPY2:%[0-9]+]]:_(s64) = COPY $d0
|
|
|
|
|
; CHECK: ADJCALLSTACKUP 0, 0, implicit-def $sp, implicit $sp
|
|
|
|
|
; CHECK: $x0 = COPY [[COPY2]](s64)
|
[GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
2017-11-14 23:42:19 +01:00
|
|
|
; CHECK: [[TRUNC:%[0-9]+]]:_(s32) = G_TRUNC [[COPY]](s64)
|
|
|
|
|
; CHECK: [[TRUNC1:%[0-9]+]]:_(s32) = G_TRUNC [[COPY1]](s64)
|
2018-01-31 23:04:26 +01:00
|
|
|
; CHECK: ADJCALLSTACKDOWN 0, 0, implicit-def $sp, implicit $sp
|
|
|
|
|
; CHECK: $s0 = COPY [[TRUNC]](s32)
|
|
|
|
|
; CHECK: $s1 = COPY [[TRUNC1]](s32)
|
|
|
|
|
; CHECK: BL &fmodf, csr_aarch64_aapcs, implicit-def $lr, implicit $sp, implicit $s0, implicit $s1, implicit-def $s0
|
|
|
|
|
; CHECK: [[COPY3:%[0-9]+]]:_(s32) = COPY $s0
|
|
|
|
|
; CHECK: ADJCALLSTACKUP 0, 0, implicit-def $sp, implicit $sp
|
|
|
|
|
; CHECK: $w0 = COPY [[COPY3]](s32)
|
2018-11-06 19:59:18 +01:00
|
|
|
%0:_(s64) = COPY $x0
|
|
|
|
|
%1:_(s64) = COPY $x1
|
|
|
|
|
%2:_(s64) = G_FREM %0, %1
|
|
|
|
|
$x0 = COPY %2(s64)
|
|
|
|
|
%3:_(s32) = G_TRUNC %0(s64)
|
|
|
|
|
%4:_(s32) = G_TRUNC %1(s64)
|
|
|
|
|
%5:_(s32) = G_FREM %3, %4
|
|
|
|
|
$w0 = COPY %5(s32)
|
2016-08-29 21:07:16 +02:00
|
|
|
|
2018-11-06 19:59:18 +01:00
|
|
|
...
|
