[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
; RUN: llc < %s -mcpu=pwr7 -mattr=+vsx | FileCheck %s
|
2014-12-05 20:32:05 +00:00
|
|
|
; RUN: llc < %s -mcpu=pwr7 -mattr=+vsx -fast-isel -O0 | FileCheck -check-prefix=CHECK-FISL %s
|
[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
|
|
|
|
; Also run with -schedule-ppc-vsx-fma-mutation-early as a stress test for the
|
|
|
|
; live-interval-updating logic.
|
|
|
|
; RUN: llc < %s -mcpu=pwr7 -mattr=+vsx -schedule-ppc-vsx-fma-mutation-early
|
|
|
|
target datalayout = "E-m:e-i64:64-n32:64"
|
|
|
|
target triple = "powerpc64-unknown-linux-gnu"
|
|
|
|
|
|
|
|
define void @test1(double %a, double %b, double %c, double %e, double* nocapture %d) #0 {
|
|
|
|
entry:
|
|
|
|
%0 = tail call double @llvm.fma.f64(double %b, double %c, double %a)
|
|
|
|
store double %0, double* %d, align 8
|
|
|
|
%1 = tail call double @llvm.fma.f64(double %b, double %e, double %a)
|
|
|
|
%arrayidx1 = getelementptr inbounds double* %d, i64 1
|
|
|
|
store double %1, double* %arrayidx1, align 8
|
|
|
|
ret void
|
|
|
|
|
|
|
|
; CHECK-LABEL: @test1
|
|
|
|
; CHECK-DAG: li [[C1:[0-9]+]], 8
|
|
|
|
; CHECK-DAG: xsmaddmdp 3, 2, 1
|
|
|
|
; CHECK-DAG: xsmaddadp 1, 2, 4
|
|
|
|
; CHECK-DAG: stxsdx 3, 0, 7
|
|
|
|
; CHECK-DAG: stxsdx 1, 7, [[C1]]
|
|
|
|
; CHECK: blr
|
2014-12-05 20:32:05 +00:00
|
|
|
|
|
|
|
; CHECK-FISL-LABEL: @test1
|
|
|
|
; CHECK-FISL-DAG: fmr 0, 1
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 0, 2, 3
|
|
|
|
; CHECK-FISL-DAG: stxsdx 0, 0, 7
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 1, 2, 4
|
|
|
|
; CHECK-FISL-DAG: li [[C1:[0-9]+]], 8
|
|
|
|
; CHECK-FISL-DAG: stxsdx 1, 7, [[C1]]
|
|
|
|
; CHECK-FISL: blr
|
[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
define void @test2(double %a, double %b, double %c, double %e, double %f, double* nocapture %d) #0 {
|
|
|
|
entry:
|
|
|
|
%0 = tail call double @llvm.fma.f64(double %b, double %c, double %a)
|
|
|
|
store double %0, double* %d, align 8
|
|
|
|
%1 = tail call double @llvm.fma.f64(double %b, double %e, double %a)
|
|
|
|
%arrayidx1 = getelementptr inbounds double* %d, i64 1
|
|
|
|
store double %1, double* %arrayidx1, align 8
|
|
|
|
%2 = tail call double @llvm.fma.f64(double %b, double %f, double %a)
|
|
|
|
%arrayidx2 = getelementptr inbounds double* %d, i64 2
|
|
|
|
store double %2, double* %arrayidx2, align 8
|
|
|
|
ret void
|
|
|
|
|
|
|
|
; CHECK-LABEL: @test2
|
|
|
|
; CHECK-DAG: li [[C1:[0-9]+]], 8
|
|
|
|
; CHECK-DAG: li [[C2:[0-9]+]], 16
|
|
|
|
; CHECK-DAG: xsmaddmdp 3, 2, 1
|
|
|
|
; CHECK-DAG: xsmaddmdp 4, 2, 1
|
|
|
|
; CHECK-DAG: xsmaddadp 1, 2, 5
|
|
|
|
; CHECK-DAG: stxsdx 3, 0, 8
|
|
|
|
; CHECK-DAG: stxsdx 4, 8, [[C1]]
|
|
|
|
; CHECK-DAG: stxsdx 1, 8, [[C2]]
|
|
|
|
; CHECK: blr
|
2014-12-05 20:32:05 +00:00
|
|
|
|
|
|
|
; CHECK-FISL-LABEL: @test2
|
|
|
|
; CHECK-FISL-DAG: fmr 0, 1
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 0, 2, 3
|
|
|
|
; CHECK-FISL-DAG: stxsdx 0, 0, 8
|
|
|
|
; CHECK-FISL-DAG: fmr 0, 1
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 0, 2, 4
|
|
|
|
; CHECK-FISL-DAG: li [[C1:[0-9]+]], 8
|
|
|
|
; CHECK-FISL-DAG: stxsdx 0, 8, [[C1]]
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 1, 2, 5
|
|
|
|
; CHECK-FISL-DAG: li [[C2:[0-9]+]], 16
|
|
|
|
; CHECK-FISL-DAG: stxsdx 1, 8, [[C2]]
|
|
|
|
; CHECK-FISL: blr
|
[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
define void @test3(double %a, double %b, double %c, double %e, double %f, double* nocapture %d) #0 {
|
|
|
|
entry:
|
|
|
|
%0 = tail call double @llvm.fma.f64(double %b, double %c, double %a)
|
|
|
|
store double %0, double* %d, align 8
|
|
|
|
%1 = tail call double @llvm.fma.f64(double %b, double %e, double %a)
|
|
|
|
%2 = tail call double @llvm.fma.f64(double %b, double %c, double %1)
|
|
|
|
%arrayidx1 = getelementptr inbounds double* %d, i64 3
|
|
|
|
store double %2, double* %arrayidx1, align 8
|
|
|
|
%3 = tail call double @llvm.fma.f64(double %b, double %f, double %a)
|
|
|
|
%arrayidx2 = getelementptr inbounds double* %d, i64 2
|
|
|
|
store double %3, double* %arrayidx2, align 8
|
|
|
|
%arrayidx3 = getelementptr inbounds double* %d, i64 1
|
|
|
|
store double %1, double* %arrayidx3, align 8
|
|
|
|
ret void
|
|
|
|
|
|
|
|
; CHECK-LABEL: @test3
|
2014-03-29 05:29:01 +00:00
|
|
|
; CHECK-DAG: fmr [[F1:[0-9]+]], 1
|
[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
; CHECK-DAG: li [[C1:[0-9]+]], 24
|
|
|
|
; CHECK-DAG: li [[C2:[0-9]+]], 16
|
|
|
|
; CHECK-DAG: li [[C3:[0-9]+]], 8
|
|
|
|
; CHECK-DAG: xsmaddmdp 4, 2, 1
|
|
|
|
; CHECK-DAG: xsmaddadp 1, 2, 5
|
|
|
|
|
|
|
|
; Note: We could convert this next FMA to M-type as well, but it would require
|
|
|
|
; re-ordering the instructions.
|
|
|
|
; CHECK-DAG: xsmaddadp [[F1]], 2, 3
|
|
|
|
|
|
|
|
; CHECK-DAG: xsmaddmdp 2, 3, 4
|
|
|
|
; CHECK-DAG: stxsdx [[F1]], 0, 8
|
|
|
|
; CHECK-DAG: stxsdx 2, 8, [[C1]]
|
|
|
|
; CHECK-DAG: stxsdx 1, 8, [[C2]]
|
|
|
|
; CHECK-DAG: stxsdx 4, 8, [[C3]]
|
2014-03-29 05:29:01 +00:00
|
|
|
; CHECK: blr
|
2014-12-05 20:32:05 +00:00
|
|
|
|
|
|
|
; CHECK-FISL-LABEL: @test3
|
|
|
|
; CHECK-FISL-DAG: fmr [[F1:[0-9]+]], 1
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp [[F1]], 2, 4
|
|
|
|
; CHECK-FISL-DAG: fmr 4, [[F1]]
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 4, 2, 3
|
|
|
|
; CHECK-FISL-DAG: li [[C1:[0-9]+]], 24
|
|
|
|
; CHECK-FISL-DAG: stxsdx 4, 8, [[C1]]
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 1, 2, 5
|
|
|
|
; CHECK-FISL-DAG: li [[C2:[0-9]+]], 16
|
|
|
|
; CHECK-FISL-DAG: stxsdx 1, 8, [[C2]]
|
|
|
|
; CHECK-FISL-DAG: li [[C3:[0-9]+]], 8
|
|
|
|
; CHECK-FISL-DAG: stxsdx 0, 8, [[C3]]
|
|
|
|
; CHECK-FISL: blr
|
[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
define void @test4(double %a, double %b, double %c, double %e, double %f, double* nocapture %d) #0 {
|
|
|
|
entry:
|
|
|
|
%0 = tail call double @llvm.fma.f64(double %b, double %c, double %a)
|
|
|
|
store double %0, double* %d, align 8
|
|
|
|
%1 = tail call double @llvm.fma.f64(double %b, double %e, double %a)
|
|
|
|
%arrayidx1 = getelementptr inbounds double* %d, i64 1
|
|
|
|
store double %1, double* %arrayidx1, align 8
|
|
|
|
%2 = tail call double @llvm.fma.f64(double %b, double %c, double %1)
|
|
|
|
%arrayidx3 = getelementptr inbounds double* %d, i64 3
|
|
|
|
store double %2, double* %arrayidx3, align 8
|
|
|
|
%3 = tail call double @llvm.fma.f64(double %b, double %f, double %a)
|
|
|
|
%arrayidx4 = getelementptr inbounds double* %d, i64 2
|
|
|
|
store double %3, double* %arrayidx4, align 8
|
|
|
|
ret void
|
|
|
|
|
|
|
|
; CHECK-LABEL: @test4
|
2014-03-29 05:29:01 +00:00
|
|
|
; CHECK-DAG: fmr [[F1:[0-9]+]], 1
|
[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
; CHECK-DAG: li [[C1:[0-9]+]], 8
|
|
|
|
; CHECK-DAG: li [[C2:[0-9]+]], 16
|
|
|
|
; CHECK-DAG: xsmaddmdp 4, 2, 1
|
|
|
|
|
|
|
|
; Note: We could convert this next FMA to M-type as well, but it would require
|
|
|
|
; re-ordering the instructions.
|
|
|
|
; CHECK-DAG: xsmaddadp 1, 2, 5
|
|
|
|
|
|
|
|
; CHECK-DAG: xsmaddadp [[F1]], 2, 3
|
|
|
|
; CHECK-DAG: stxsdx [[F1]], 0, 8
|
|
|
|
; CHECK-DAG: stxsdx 4, 8, [[C1]]
|
|
|
|
; CHECK-DAG: li [[C3:[0-9]+]], 24
|
|
|
|
; CHECK-DAG: xsmaddadp 4, 2, 3
|
|
|
|
; CHECK-DAG: stxsdx 4, 8, [[C3]]
|
|
|
|
; CHECK-DAG: stxsdx 1, 8, [[C2]]
|
|
|
|
; CHECK: blr
|
2014-12-05 20:32:05 +00:00
|
|
|
|
|
|
|
; CHECK-FISL-LABEL: @test4
|
|
|
|
; CHECK-FISL-DAG: fmr [[F1:[0-9]+]], 1
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp [[F1]], 2, 3
|
|
|
|
; CHECK-FISL-DAG: stxsdx 0, 0, 8
|
|
|
|
; CHECK-FISL-DAG: fmr [[F1]], 1
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp [[F1]], 2, 4
|
|
|
|
; CHECK-FISL-DAG: li [[C3:[0-9]+]], 8
|
|
|
|
; CHECK-FISL-DAG: stxsdx 0, 8, [[C3]]
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 0, 2, 3
|
|
|
|
; CHECK-FISL-DAG: li [[C1:[0-9]+]], 24
|
|
|
|
; CHECK-FISL-DAG: stxsdx 0, 8, [[C1]]
|
|
|
|
; CHECK-FISL-DAG: xsmaddadp 1, 2, 5
|
|
|
|
; CHECK-FISL-DAG: li [[C2:[0-9]+]], 16
|
|
|
|
; CHECK-FISL-DAG: stxsdx 1, 8, [[C2]]
|
|
|
|
; CHECK-FISL: blr
|
[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
declare double @llvm.fma.f64(double, double, double) #0
|
|
|
|
|
2014-03-29 05:29:01 +00:00
|
|
|
define void @testv1(<2 x double> %a, <2 x double> %b, <2 x double> %c, <2 x double> %e, <2 x double>* nocapture %d) #0 {
|
|
|
|
entry:
|
|
|
|
%0 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %c, <2 x double> %a)
|
|
|
|
store <2 x double> %0, <2 x double>* %d, align 8
|
|
|
|
%1 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %e, <2 x double> %a)
|
|
|
|
%arrayidx1 = getelementptr inbounds <2 x double>* %d, i64 1
|
|
|
|
store <2 x double> %1, <2 x double>* %arrayidx1, align 8
|
|
|
|
ret void
|
|
|
|
|
|
|
|
; CHECK-LABEL: @testv1
|
|
|
|
; CHECK-DAG: xvmaddmdp 36, 35, 34
|
|
|
|
; CHECK-DAG: xvmaddadp 34, 35, 37
|
|
|
|
; CHECK-DAG: li [[C1:[0-9]+]], 16
|
|
|
|
; CHECK-DAG: stxvd2x 36, 0, 3
|
|
|
|
; CHECK-DAG: stxvd2x 34, 3, [[C1:[0-9]+]]
|
|
|
|
; CHECK: blr
|
2014-12-05 20:32:05 +00:00
|
|
|
|
|
|
|
; CHECK-FISL-LABEL: @testv1
|
|
|
|
; CHECK-FISL-DAG: xxlor 0, 34, 34
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp 0, 35, 36
|
|
|
|
; CHECK-FISL-DAG: stxvd2x 0, 0, 3
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp 34, 35, 37
|
|
|
|
; CHECK-FISL-DAG: li [[C1:[0-9]+]], 16
|
|
|
|
; CHECK-FISL-DAG: stxvd2x 34, 3, [[C1:[0-9]+]]
|
|
|
|
; CHECK-FISL: blr
|
2014-03-29 05:29:01 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
define void @testv2(<2 x double> %a, <2 x double> %b, <2 x double> %c, <2 x double> %e, <2 x double> %f, <2 x double>* nocapture %d) #0 {
|
|
|
|
entry:
|
|
|
|
%0 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %c, <2 x double> %a)
|
|
|
|
store <2 x double> %0, <2 x double>* %d, align 8
|
|
|
|
%1 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %e, <2 x double> %a)
|
|
|
|
%arrayidx1 = getelementptr inbounds <2 x double>* %d, i64 1
|
|
|
|
store <2 x double> %1, <2 x double>* %arrayidx1, align 8
|
|
|
|
%2 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %f, <2 x double> %a)
|
|
|
|
%arrayidx2 = getelementptr inbounds <2 x double>* %d, i64 2
|
|
|
|
store <2 x double> %2, <2 x double>* %arrayidx2, align 8
|
|
|
|
ret void
|
|
|
|
|
|
|
|
; CHECK-LABEL: @testv2
|
|
|
|
; CHECK-DAG: xvmaddmdp 36, 35, 34
|
|
|
|
; CHECK-DAG: xvmaddmdp 37, 35, 34
|
|
|
|
; CHECK-DAG: li [[C1:[0-9]+]], 16
|
|
|
|
; CHECK-DAG: li [[C2:[0-9]+]], 32
|
|
|
|
; CHECK-DAG: xvmaddadp 34, 35, 38
|
|
|
|
; CHECK-DAG: stxvd2x 36, 0, 3
|
|
|
|
; CHECK-DAG: stxvd2x 37, 3, [[C1:[0-9]+]]
|
|
|
|
; CHECK-DAG: stxvd2x 34, 3, [[C2:[0-9]+]]
|
|
|
|
; CHECK: blr
|
2014-12-05 20:32:05 +00:00
|
|
|
|
|
|
|
; CHECK-FISL-LABEL: @testv2
|
|
|
|
; CHECK-FISL-DAG: xxlor 0, 34, 34
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp 0, 35, 36
|
|
|
|
; CHECK-FISL-DAG: stxvd2x 0, 0, 3
|
|
|
|
; CHECK-FISL-DAG: xxlor 0, 34, 34
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp 0, 35, 37
|
|
|
|
; CHECK-FISL-DAG: li [[C1:[0-9]+]], 16
|
|
|
|
; CHECK-FISL-DAG: stxvd2x 0, 3, [[C1:[0-9]+]]
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp 34, 35, 38
|
|
|
|
; CHECK-FISL-DAG: li [[C2:[0-9]+]], 32
|
|
|
|
; CHECK-FISL-DAG: stxvd2x 34, 3, [[C2:[0-9]+]]
|
|
|
|
; CHECK-FISL: blr
|
2014-03-29 05:29:01 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
define void @testv3(<2 x double> %a, <2 x double> %b, <2 x double> %c, <2 x double> %e, <2 x double> %f, <2 x double>* nocapture %d) #0 {
|
|
|
|
entry:
|
|
|
|
%0 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %c, <2 x double> %a)
|
|
|
|
store <2 x double> %0, <2 x double>* %d, align 8
|
|
|
|
%1 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %e, <2 x double> %a)
|
|
|
|
%2 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %c, <2 x double> %1)
|
|
|
|
%arrayidx1 = getelementptr inbounds <2 x double>* %d, i64 3
|
|
|
|
store <2 x double> %2, <2 x double>* %arrayidx1, align 8
|
|
|
|
%3 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %f, <2 x double> %a)
|
|
|
|
%arrayidx2 = getelementptr inbounds <2 x double>* %d, i64 2
|
|
|
|
store <2 x double> %3, <2 x double>* %arrayidx2, align 8
|
|
|
|
%arrayidx3 = getelementptr inbounds <2 x double>* %d, i64 1
|
|
|
|
store <2 x double> %1, <2 x double>* %arrayidx3, align 8
|
|
|
|
ret void
|
|
|
|
|
[PowerPC] Add vec_vsx_ld and vec_vsx_st intrinsics
This patch enables the vec_vsx_ld and vec_vsx_st intrinsics for
PowerPC, which provide programmer access to the lxvd2x, lxvw4x,
stxvd2x, and stxvw4x instructions.
New LLVM intrinsics are provided to represent these four instructions
in IntrinsicsPowerPC.td. These are patterned after the similar
intrinsics for lvx and stvx (Altivec). In PPCInstrVSX.td, these
intrinsics are tied to the code gen patterns, with additional patterns
to allow plain vanilla loads and stores to still generate these
instructions.
At -O1 and higher the intrinsics are immediately converted to loads
and stores in InstCombineCalls.cpp. This will open up more
optimization opportunities while still allowing the correct
instructions to be generated. (Similar code exists for aligned
Altivec loads and stores.)
The new intrinsics are added to the code that checks for consecutive
loads and stores in PPCISelLowering.cpp, as well as to
PPCTargetLowering::getTgtMemIntrinsic().
There's a new test to verify the correct instructions are generated.
The loads and stores tend to be reordered, so the test just counts
their number. It runs at -O2, as it's not very effective to test this
at -O0, when many unnecessary loads and stores are generated.
I ended up having to modify vsx-fma-m.ll. It turns out this test case
is slightly unreliable, but I don't know a good way to prevent
problems with it. The xvmaddmdp instructions read and write the same
register, which is one of the multiplicands. Commutativity allows
either to be chosen. If the FMAs are reordered differently than
expected by the test, the register assignment can be different as a
result. Hopefully this doesn't change often.
There is a companion patch for Clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221767 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-12 04:19:40 +00:00
|
|
|
; Note: There is some unavoidable changeability in this variant. If the
|
|
|
|
; FMAs are reordered differently, the algorithm can pick a different
|
|
|
|
; multiplicand to destroy, changing the register assignment. There isn't
|
|
|
|
; a good way to express this possibility, so hopefully this doesn't change
|
|
|
|
; too often.
|
|
|
|
|
2014-03-29 05:29:01 +00:00
|
|
|
; CHECK-LABEL: @testv3
|
|
|
|
; CHECK-DAG: xxlor [[V1:[0-9]+]], 34, 34
|
|
|
|
; CHECK-DAG: li [[C1:[0-9]+]], 48
|
|
|
|
; CHECK-DAG: li [[C2:[0-9]+]], 32
|
[PowerPC] Add vec_vsx_ld and vec_vsx_st intrinsics
This patch enables the vec_vsx_ld and vec_vsx_st intrinsics for
PowerPC, which provide programmer access to the lxvd2x, lxvw4x,
stxvd2x, and stxvw4x instructions.
New LLVM intrinsics are provided to represent these four instructions
in IntrinsicsPowerPC.td. These are patterned after the similar
intrinsics for lvx and stvx (Altivec). In PPCInstrVSX.td, these
intrinsics are tied to the code gen patterns, with additional patterns
to allow plain vanilla loads and stores to still generate these
instructions.
At -O1 and higher the intrinsics are immediately converted to loads
and stores in InstCombineCalls.cpp. This will open up more
optimization opportunities while still allowing the correct
instructions to be generated. (Similar code exists for aligned
Altivec loads and stores.)
The new intrinsics are added to the code that checks for consecutive
loads and stores in PPCISelLowering.cpp, as well as to
PPCTargetLowering::getTgtMemIntrinsic().
There's a new test to verify the correct instructions are generated.
The loads and stores tend to be reordered, so the test just counts
their number. It runs at -O2, as it's not very effective to test this
at -O0, when many unnecessary loads and stores are generated.
I ended up having to modify vsx-fma-m.ll. It turns out this test case
is slightly unreliable, but I don't know a good way to prevent
problems with it. The xvmaddmdp instructions read and write the same
register, which is one of the multiplicands. Commutativity allows
either to be chosen. If the FMAs are reordered differently than
expected by the test, the register assignment can be different as a
result. Hopefully this doesn't change often.
There is a companion patch for Clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221767 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-12 04:19:40 +00:00
|
|
|
; CHECK-DAG: xvmaddmdp 37, 35, 34
|
2014-03-29 05:29:01 +00:00
|
|
|
; CHECK-DAG: li [[C3:[0-9]+]], 16
|
|
|
|
|
|
|
|
; Note: We could convert this next FMA to M-type as well, but it would require
|
|
|
|
; re-ordering the instructions.
|
|
|
|
; CHECK-DAG: xvmaddadp [[V1]], 35, 36
|
|
|
|
|
2015-02-01 19:07:41 +00:00
|
|
|
; CHECK-DAG: xvmaddmdp 35, 36, 37
|
[PowerPC] Add vec_vsx_ld and vec_vsx_st intrinsics
This patch enables the vec_vsx_ld and vec_vsx_st intrinsics for
PowerPC, which provide programmer access to the lxvd2x, lxvw4x,
stxvd2x, and stxvw4x instructions.
New LLVM intrinsics are provided to represent these four instructions
in IntrinsicsPowerPC.td. These are patterned after the similar
intrinsics for lvx and stvx (Altivec). In PPCInstrVSX.td, these
intrinsics are tied to the code gen patterns, with additional patterns
to allow plain vanilla loads and stores to still generate these
instructions.
At -O1 and higher the intrinsics are immediately converted to loads
and stores in InstCombineCalls.cpp. This will open up more
optimization opportunities while still allowing the correct
instructions to be generated. (Similar code exists for aligned
Altivec loads and stores.)
The new intrinsics are added to the code that checks for consecutive
loads and stores in PPCISelLowering.cpp, as well as to
PPCTargetLowering::getTgtMemIntrinsic().
There's a new test to verify the correct instructions are generated.
The loads and stores tend to be reordered, so the test just counts
their number. It runs at -O2, as it's not very effective to test this
at -O0, when many unnecessary loads and stores are generated.
I ended up having to modify vsx-fma-m.ll. It turns out this test case
is slightly unreliable, but I don't know a good way to prevent
problems with it. The xvmaddmdp instructions read and write the same
register, which is one of the multiplicands. Commutativity allows
either to be chosen. If the FMAs are reordered differently than
expected by the test, the register assignment can be different as a
result. Hopefully this doesn't change often.
There is a companion patch for Clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221767 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-12 04:19:40 +00:00
|
|
|
; CHECK-DAG: xvmaddadp 34, 35, 38
|
2014-03-29 05:29:01 +00:00
|
|
|
; CHECK-DAG: stxvd2x 32, 0, 3
|
2015-02-01 19:07:41 +00:00
|
|
|
; CHECK-DAG: stxvd2x 35, 3, [[C1]]
|
2014-03-29 05:29:01 +00:00
|
|
|
; CHECK-DAG: stxvd2x 34, 3, [[C2]]
|
|
|
|
; CHECK-DAG: stxvd2x 37, 3, [[C3]]
|
|
|
|
; CHECK: blr
|
2014-12-05 20:32:05 +00:00
|
|
|
|
|
|
|
; CHECK-FISL-LABEL: @testv3
|
|
|
|
; CHECK-FISL-DAG: xxlor [[V1:[0-9]+]], 34, 34
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp [[V1]], 35, 36
|
|
|
|
; CHECK-FISL-DAG: stxvd2x [[V1]], 0, 3
|
|
|
|
; CHECK-FISL-DAG: xxlor [[V2:[0-9]+]], 34, 34
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp [[V2]], 35, 37
|
|
|
|
; CHECK-FISL-DAG: xxlor [[V3:[0-9]+]], 0, 0
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp [[V3]], 35, 36
|
|
|
|
; CHECK-FISL-DAG: li [[C1:[0-9]+]], 48
|
|
|
|
; CHECK-FISL-DAG: stxvd2x [[V3]], 3, [[C1]]
|
|
|
|
; CHECK-FISL-DAG: xvmaddadp 34, 35, 38
|
|
|
|
; CHECK-FISL-DAG: li [[C2:[0-9]+]], 32
|
|
|
|
; CHECK-FISL-DAG: stxvd2x 34, 3, [[C2]]
|
|
|
|
; CHECK-FISL-DAG: li [[C3:[0-9]+]], 16
|
|
|
|
; CHECK-FISL-DAG: stxvd2x 0, 3, [[C3]]
|
|
|
|
; CHECK-FISL: blr
|
2014-03-29 05:29:01 +00:00
|
|
|
}
|
|
|
|
|
|
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define void @testv4(<2 x double> %a, <2 x double> %b, <2 x double> %c, <2 x double> %e, <2 x double> %f, <2 x double>* nocapture %d) #0 {
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entry:
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%0 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %c, <2 x double> %a)
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store <2 x double> %0, <2 x double>* %d, align 8
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%1 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %e, <2 x double> %a)
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%arrayidx1 = getelementptr inbounds <2 x double>* %d, i64 1
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store <2 x double> %1, <2 x double>* %arrayidx1, align 8
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%2 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %c, <2 x double> %1)
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%arrayidx3 = getelementptr inbounds <2 x double>* %d, i64 3
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store <2 x double> %2, <2 x double>* %arrayidx3, align 8
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%3 = tail call <2 x double> @llvm.fma.v2f64(<2 x double> %b, <2 x double> %f, <2 x double> %a)
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%arrayidx4 = getelementptr inbounds <2 x double>* %d, i64 2
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store <2 x double> %3, <2 x double>* %arrayidx4, align 8
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ret void
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; CHECK-LABEL: @testv4
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; CHECK-DAG: xxlor [[V1:[0-9]+]], 34, 34
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; CHECK-DAG: xvmaddmdp 37, 35, 34
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; CHECK-DAG: li [[C1:[0-9]+]], 16
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; CHECK-DAG: li [[C2:[0-9]+]], 32
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; CHECK-DAG: xvmaddadp 34, 35, 38
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; Note: We could convert this next FMA to M-type as well, but it would require
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; re-ordering the instructions.
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; CHECK-DAG: xvmaddadp [[V1]], 35, 36
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; CHECK-DAG: stxvd2x 32, 0, 3
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; CHECK-DAG: stxvd2x 37, 3, [[C1]]
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; CHECK-DAG: li [[C3:[0-9]+]], 48
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; CHECK-DAG: xvmaddadp 37, 35, 36
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; CHECK-DAG: stxvd2x 37, 3, [[C3]]
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; CHECK-DAG: stxvd2x 34, 3, [[C2]]
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; CHECK: blr
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2014-12-05 20:32:05 +00:00
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; CHECK-FISL-LABEL: @testv4
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; CHECK-FISL-DAG: xxlor [[V1:[0-9]+]], 34, 34
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; CHECK-FISL-DAG: xvmaddadp [[V1]], 35, 36
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; CHECK-FISL-DAG: stxvd2x 0, 0, 3
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; CHECK-FISL-DAG: xxlor [[V2:[0-9]+]], 34, 34
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; CHECK-FISL-DAG: xvmaddadp [[V2]], 35, 37
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; CHECK-FISL-DAG: li [[C1:[0-9]+]], 16
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; CHECK-FISL-DAG: stxvd2x 0, 3, [[C1]]
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; CHECK-FISL-DAG: xvmaddadp 0, 35, 37
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; CHECK-FISL-DAG: li [[C3:[0-9]+]], 48
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; CHECK-FISL-DAG: stxvd2x 0, 3, [[C3]]
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; CHECK-FISL-DAG: xvmaddadp 0, 35, 36
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; CHECK-FISL-DAG: li [[C2:[0-9]+]], 32
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; CHECK-FISL-DAG: stxvd2x 34, 3, [[C2]]
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; CHECK-FISL: blr
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2014-03-29 05:29:01 +00:00
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}
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declare <2 x double> @llvm.fma.v2f64(<2 x double>, <2 x double>, <2 x double>) #0
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[PowerPC] Select between VSX A-type and M-type FMA instructions just before RA
The VSX instruction set has two types of FMA instructions: A-type (where the
addend is taken from the output register) and M-type (where one of the product
operands is taken from the output register). This adds a small pass that runs
just after MI scheduling (and, thus, just before register allocation) that
mutates A-type instructions (that are created during isel) into M-type
instructions when:
1. This will eliminate an otherwise-necessary copy of the addend
2. One of the product operands is killed by the instruction
The "right" moment to make this decision is in between scheduling and register
allocation, because only there do we know whether or not one of the product
operands is killed by any particular instruction. Unfortunately, this also
makes the implementation somewhat complicated, because the MIs are not in SSA
form and we need to preserve the LiveIntervals analysis.
As a simple example, if we have:
%vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
...
%vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
%RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
...
We can eliminate the copy by changing from the A-type to the
M-type instruction. This means:
%vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
%RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
is replaced by:
%vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
%RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204768 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:29:21 +00:00
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attributes #0 = { nounwind readnone }
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