cde083e010
FixIrreducibleControlFlow pass adds dispatch blocks with a `br_table`
that has multiple predecessors and successors, because it serves as
something like a traffic hub for BBs. As a result of this, there can be
register uses that are not dominated by a def in every path from the
entry block. For example, suppose register %a is defined in BB1 and used
in BB2, and there is a single path from BB1 and BB2:
```
BB1 -> ... -> BB2
```
After FixIrreducibleControlFlow runs, there can be a dispatch block
between these two BBs:
```
BB1 -> ... -> Dispatch -> ... -> BB2
```
And this dispatch block has multiple predecessors, now
there is a path to BB2 that does not first visit BB1, and in that path
%a is not dominated by a def anymore.
To fix this problem, we have been adding `IMPLICIT_DEF`s to all
registers in PrepareForLiveInternals pass, and then remove unnecessary
ones in OptimizeLiveIntervals pass after computing `LiveIntervals`. But
FixIrreducibleControlFlow pass itself ends up violating register use-def
relationship, resulting in invalid code. This was OK so far because
MIR verifier apparently didn't check this in validation. But @arsenm
fixed this and it caught this bug in validation
(https://github.com/llvm/llvm-project/issues/55249).
This CL moves the `IMPLICIT_DEF` adding routine from
PrepareForLiveInternals to FixIrreducibleControlFlow. We only run it
when FixIrreducibleControlFlow changes the code. And then
PrepareForLiveInternals doesn't do anything other than setting
`TracksLiveness` property, which is a prerequisite for running
`LiveIntervals` analysis, which is required by the next pass
OptimizeLiveIntervals.
But in our backend we don't seem to do anything that invalidates this up
until OptimizeLiveIntervals, and I'm not sure why we are calling
`invalidateLiveness` in ReplacePhysRegs pass, because what that pass
does is to replace physical registers with virtual ones 1-to-1. I
deleted the `invalidateLiveness` call there and we don't need to set
that flag explicitly, which obviates all the need for
PrepareForLiveInternals.
(By the way, This 'Liveness' here is different from `LiveIntervals`
analysis. Setting this only means BBs' live-in info is correct, all uses
are dominated by defs, `kill` flag is conservatively correct, which
means if there is a `kill` flag set it should be the last use. See
2a0837aab1/llvm/include/llvm/CodeGen/MachineFunction.h (L125-L134)
for details.)
So this CL removes PrepareForLiveInternals pass altogether. Something
similar to this was attempted by D56091 long ago but that came short of
actually removing the pass, and I couldn't land it because
FixIrreducibleControlFlow violated use-def relationship, which this CL
fixes.
This doesn't change output in any meaningful way. All test changes
except `irreducible-cfg.mir` are register numbering.
Also this will likely to reduce compilation time, because we have been
adding `IMPLICIT_DEF` for all registers every time `-O2` is given, but
now we do that only when there is irreducible control flow, which is
rare.
Fixes https://github.com/llvm/llvm-project/issues/55249.
Reviewed By: dschuff, kripken
Differential Revision: https://reviews.llvm.org/D125515
678 lines
23 KiB
LLVM
678 lines
23 KiB
LLVM
; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -verify-machineinstrs | FileCheck %s
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; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -verify-machineinstrs | FileCheck %s --check-prefix=NOREGS
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; Test the register stackifier pass.
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; We have two sets of tests, one with registers and implicit locals, and
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; a stack / explicit locals based version (NOREGS).
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target triple = "wasm32-unknown-unknown"
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; No because of pointer aliasing.
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; CHECK-LABEL: no0:
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; CHECK: return $1{{$}}
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; NOREGS-LABEL: no0:
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; NOREGS: return{{$}}
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define i32 @no0(i32* %p, i32* %q) {
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%t = load i32, i32* %q
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store i32 0, i32* %p
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ret i32 %t
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}
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; No because of side effects.
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; CHECK-LABEL: no1:
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; CHECK: return $1{{$}}
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; NOREGS-LABEL: no1:
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; NOREGS: return{{$}}
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define i32 @no1(i32* %p, i32* dereferenceable(4) %q) {
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%t = load volatile i32, i32* %q, !invariant.load !0
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store volatile i32 0, i32* %p
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ret i32 %t
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}
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; Yes because of invariant load and no side effects.
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; CHECK-LABEL: yes0:
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; CHECK: return $pop{{[0-9]+}}{{$}}
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; NOREGS-LABEL: yes0:
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; NOREGS: return{{$}}
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define i32 @yes0(i32* %p, i32* dereferenceable(4) %q) {
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%t = load i32, i32* %q, !invariant.load !0
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store i32 0, i32* %p
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ret i32 %t
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}
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; Yes because of no intervening side effects.
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; CHECK-LABEL: yes1:
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; CHECK: return $pop0{{$}}
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; NOREGS-LABEL: yes1:
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; NOREGS: return{{$}}
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define i32 @yes1(i32* %q) {
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%t = load volatile i32, i32* %q
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ret i32 %t
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}
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; Yes because undefined behavior can be sunk past a store.
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; CHECK-LABEL: sink_trap:
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; CHECK: return $pop{{[0-9]+}}{{$}}
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; NOREGS-LABEL: sink_trap:
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; NOREGS: return{{$}}
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define i32 @sink_trap(i32 %x, i32 %y, i32* %p) {
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%t = sdiv i32 %x, %y
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store volatile i32 0, i32* %p
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ret i32 %t
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}
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; Yes because the call is readnone.
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; CHECK-LABEL: sink_readnone_call:
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; CHECK: return $pop1{{$}}
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; NOREGS-LABEL: sink_readnone_call:
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; NOREGS: return{{$}}
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declare i32 @readnone_callee() readnone nounwind
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define i32 @sink_readnone_call(i32 %x, i32 %y, i32* %p) {
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%t = call i32 @readnone_callee()
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store volatile i32 0, i32* %p
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ret i32 %t
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}
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; No because the call is readonly and there's an intervening store.
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; CHECK-LABEL: no_sink_readonly_call:
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; CHECK: return ${{[0-9]+}}{{$}}
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; NOREGS-LABEL: no_sink_readonly_call:
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; NOREGS: return{{$}}
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declare i32 @readonly_callee() readonly nounwind
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define i32 @no_sink_readonly_call(i32 %x, i32 %y, i32* %p) {
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%t = call i32 @readonly_callee()
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store i32 0, i32* %p
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ret i32 %t
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}
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; Don't schedule stack uses into the stack. To reduce register pressure, the
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; scheduler might be tempted to move the definition of $2 down. However, this
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; would risk getting incorrect liveness if the instructions are later
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; rearranged to make the stack contiguous.
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; CHECK-LABEL: stack_uses:
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; CHECK: .functype stack_uses (i32, i32, i32, i32) -> (i32){{$}}
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; CHECK-NEXT: block {{$}}
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; CHECK-NEXT: i32.const $push[[L13:[0-9]+]]=, 1{{$}}
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; CHECK-NEXT: i32.lt_s $push[[L0:[0-9]+]]=, $0, $pop[[L13]]{{$}}
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; CHECK-NEXT: i32.const $push[[L1:[0-9]+]]=, 2{{$}}
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; CHECK-NEXT: i32.lt_s $push[[L2:[0-9]+]]=, $1, $pop[[L1]]{{$}}
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; CHECK-NEXT: i32.xor $push[[L5:[0-9]+]]=, $pop[[L0]], $pop[[L2]]{{$}}
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; CHECK-NEXT: i32.const $push[[L12:[0-9]+]]=, 1{{$}}
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; CHECK-NEXT: i32.lt_s $push[[L3:[0-9]+]]=, $2, $pop[[L12]]{{$}}
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; CHECK-NEXT: i32.const $push[[L11:[0-9]+]]=, 2{{$}}
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; CHECK-NEXT: i32.lt_s $push[[L4:[0-9]+]]=, $3, $pop[[L11]]{{$}}
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; CHECK-NEXT: i32.xor $push[[L6:[0-9]+]]=, $pop[[L3]], $pop[[L4]]{{$}}
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; CHECK-NEXT: i32.eq $push7=, $pop[[L5]], $pop[[L6]]{{$}}
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; CHECK-NEXT: br_if 0, $pop7{{$}}
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; CHECK-NEXT: i32.const $push8=, 0{{$}}
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; CHECK-NEXT: return $pop8{{$}}
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; CHECK-NEXT: .LBB{{[0-9]+}}_2:
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; CHECK-NEXT: end_block{{$}}
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; CHECK-NEXT: i32.const $push12=, 1{{$}}
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; CHECK-NEXT: return $pop12{{$}}
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; NOREGS-LABEL: stack_uses:
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; NOREGS: .functype stack_uses (i32, i32, i32, i32) -> (i32){{$}}
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; NOREGS-NEXT: block {{$}}
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; NOREGS-NEXT: local.get 0{{$}}
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; NOREGS-NEXT: i32.const 1{{$}}
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; NOREGS-NEXT: i32.lt_s
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; NOREGS-NEXT: local.get 1{{$}}
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; NOREGS-NEXT: i32.const 2{{$}}
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; NOREGS-NEXT: i32.lt_s
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; NOREGS-NEXT: i32.xor {{$}}
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; NOREGS-NEXT: local.get 2{{$}}
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; NOREGS-NEXT: i32.const 1{{$}}
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; NOREGS-NEXT: i32.lt_s
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; NOREGS-NEXT: local.get 3{{$}}
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; NOREGS-NEXT: i32.const 2{{$}}
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; NOREGS-NEXT: i32.lt_s
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; NOREGS-NEXT: i32.xor {{$}}
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; NOREGS-NEXT: i32.eq {{$}}
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; NOREGS-NEXT: br_if 0{{$}}
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; NOREGS-NEXT: i32.const 0{{$}}
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; NOREGS-NEXT: return{{$}}
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; NOREGS-NEXT: .LBB{{[0-9]+}}_2:
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; NOREGS-NEXT: end_block{{$}}
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; NOREGS-NEXT: i32.const 1{{$}}
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; NOREGS-NEXT: return{{$}}
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define i32 @stack_uses(i32 %x, i32 %y, i32 %z, i32 %w) {
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entry:
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%c = icmp sle i32 %x, 0
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%d = icmp sle i32 %y, 1
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%e = icmp sle i32 %z, 0
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%f = icmp sle i32 %w, 1
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%g = xor i1 %c, %d
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%h = xor i1 %e, %f
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%i = xor i1 %g, %h
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br i1 %i, label %true, label %false
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true:
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ret i32 0
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false:
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ret i32 1
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}
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; Test an interesting case where the load has multiple uses and cannot
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; be trivially stackified. However, it can be stackified with a local.tee.
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; CHECK-LABEL: multiple_uses:
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; CHECK: .functype multiple_uses (i32, i32, i32) -> (){{$}}
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; CHECK-NEXT: block {{$}}
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; CHECK-NEXT: i32.load $push[[NUM0:[0-9]+]]=, 0($2){{$}}
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; CHECK-NEXT: local.tee $push[[NUM1:[0-9]+]]=, $3=, $pop[[NUM0]]{{$}}
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; CHECK-NEXT: i32.ge_u $push[[NUM2:[0-9]+]]=, $pop[[NUM1]], $1{{$}}
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; CHECK-NEXT: br_if 0, $pop[[NUM2]]{{$}}
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; CHECK-NEXT: i32.lt_u $push[[NUM3:[0-9]+]]=, $3, $0{{$}}
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; CHECK-NEXT: br_if 0, $pop[[NUM3]]{{$}}
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; CHECK-NEXT: i32.store 0($2), $3{{$}}
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; CHECK-NEXT: .LBB{{[0-9]+}}_3:
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; CHECK-NEXT: end_block{{$}}
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; CHECK-NEXT: return{{$}}
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; NOREGS-LABEL: multiple_uses:
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; NOREGS: .functype multiple_uses (i32, i32, i32) -> (){{$}}
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; NOREGS: .local i32{{$}}
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; NOREGS-NEXT: block {{$}}
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; NOREGS-NEXT: local.get 2{{$}}
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; NOREGS-NEXT: i32.load 0{{$}}
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; NOREGS-NEXT: local.tee 3{{$}}
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; NOREGS-NEXT: local.get 1{{$}}
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; NOREGS-NEXT: i32.ge_u
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; NOREGS-NEXT: br_if 0{{$}}
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; NOREGS-NEXT: local.get 3{{$}}
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; NOREGS-NEXT: local.get 0{{$}}
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; NOREGS-NEXT: i32.lt_u
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; NOREGS-NEXT: br_if 0{{$}}
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; NOREGS-NEXT: local.get 2{{$}}
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; NOREGS-NEXT: local.get 3{{$}}
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; NOREGS-NEXT: i32.store 0{{$}}
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; NOREGS-NEXT: .LBB{{[0-9]+}}_3:
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; NOREGS-NEXT: end_block{{$}}
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; NOREGS-NEXT: return{{$}}
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define void @multiple_uses(i32* %arg0, i32* %arg1, i32* %arg2) nounwind {
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bb:
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br label %loop
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loop:
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%tmp7 = load i32, i32* %arg2
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%tmp8 = inttoptr i32 %tmp7 to i32*
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%tmp9 = icmp uge i32* %tmp8, %arg1
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%tmp10 = icmp ult i32* %tmp8, %arg0
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%tmp11 = or i1 %tmp9, %tmp10
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br i1 %tmp11, label %back, label %then
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then:
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store i32 %tmp7, i32* %arg2
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br label %back
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back:
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br i1 undef, label %return, label %loop
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return:
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ret void
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}
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; Don't stackify stores effects across other instructions with side effects.
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; CHECK: side_effects:
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; CHECK: store
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; CHECK: call
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; CHECK: store
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; CHECK-NEXT: call
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; NOREGS: side_effects:
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; NOREGS: store
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; NOREGS: call
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; NOREGS: store
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; NOREGS-NEXT: call
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declare void @evoke_side_effects()
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define hidden void @stackify_store_across_side_effects(double* nocapture %d) {
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entry:
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store double 2.0, double* %d
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call void @evoke_side_effects()
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store double 2.0, double* %d
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call void @evoke_side_effects()
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ret void
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}
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; Div instructions have side effects and can't be reordered, but this entire
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; function should still be able to be stackified because it's already in
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; tree order.
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; CHECK-LABEL: div_tree:
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; CHECK: .functype div_tree (i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32) -> (i32){{$}}
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; CHECK-NEXT: i32.div_s $push[[L0:[0-9]+]]=, $0, $1{{$}}
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; CHECK-NEXT: i32.div_s $push[[L1:[0-9]+]]=, $2, $3{{$}}
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; CHECK-NEXT: i32.div_s $push[[L2:[0-9]+]]=, $pop[[L0]], $pop[[L1]]{{$}}
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; CHECK-NEXT: i32.div_s $push[[L3:[0-9]+]]=, $4, $5{{$}}
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; CHECK-NEXT: i32.div_s $push[[L4:[0-9]+]]=, $6, $7{{$}}
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; CHECK-NEXT: i32.div_s $push[[L5:[0-9]+]]=, $pop[[L3]], $pop[[L4]]{{$}}
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; CHECK-NEXT: i32.div_s $push[[L6:[0-9]+]]=, $pop[[L2]], $pop[[L5]]{{$}}
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; CHECK-NEXT: i32.div_s $push[[L7:[0-9]+]]=, $8, $9{{$}}
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; CHECK-NEXT: i32.div_s $push[[L8:[0-9]+]]=, $10, $11{{$}}
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; CHECK-NEXT: i32.div_s $push[[L9:[0-9]+]]=, $pop[[L7]], $pop[[L8]]{{$}}
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; CHECK-NEXT: i32.div_s $push[[L10:[0-9]+]]=, $12, $13{{$}}
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; CHECK-NEXT: i32.div_s $push[[L11:[0-9]+]]=, $14, $15{{$}}
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; CHECK-NEXT: i32.div_s $push[[L12:[0-9]+]]=, $pop[[L10]], $pop[[L11]]{{$}}
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; CHECK-NEXT: i32.div_s $push[[L13:[0-9]+]]=, $pop[[L9]], $pop[[L12]]{{$}}
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; CHECK-NEXT: i32.div_s $push[[L14:[0-9]+]]=, $pop[[L6]], $pop[[L13]]{{$}}
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; CHECK-NEXT: return $pop[[L14]]{{$}}
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; NOREGS-LABEL: div_tree:
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; NOREGS: .functype div_tree (i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32, i32) -> (i32){{$}}
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; NOREGS-NEXT: local.get 0{{$}}
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; NOREGS-NEXT: local.get 1{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: local.get 2{{$}}
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; NOREGS-NEXT: local.get 3{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: local.get 4{{$}}
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; NOREGS-NEXT: local.get 5{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: local.get 6{{$}}
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; NOREGS-NEXT: local.get 7{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: local.get 8{{$}}
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; NOREGS-NEXT: local.get 9{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: local.get 10{{$}}
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; NOREGS-NEXT: local.get 11{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: local.get 12{{$}}
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; NOREGS-NEXT: local.get 13{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: local.get 14{{$}}
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; NOREGS-NEXT: local.get 15{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: i32.div_s{{$}}
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; NOREGS-NEXT: return{{$}}
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define i32 @div_tree(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f, i32 %g, i32 %h, i32 %i, i32 %j, i32 %k, i32 %l, i32 %m, i32 %n, i32 %o, i32 %p) {
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entry:
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%div = sdiv i32 %a, %b
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%div1 = sdiv i32 %c, %d
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%div2 = sdiv i32 %div, %div1
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%div3 = sdiv i32 %e, %f
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%div4 = sdiv i32 %g, %h
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%div5 = sdiv i32 %div3, %div4
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%div6 = sdiv i32 %div2, %div5
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%div7 = sdiv i32 %i, %j
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%div8 = sdiv i32 %k, %l
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%div9 = sdiv i32 %div7, %div8
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%div10 = sdiv i32 %m, %n
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%div11 = sdiv i32 %o, %p
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%div12 = sdiv i32 %div10, %div11
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%div13 = sdiv i32 %div9, %div12
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%div14 = sdiv i32 %div6, %div13
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ret i32 %div14
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}
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; A simple multiple-use case.
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; CHECK-LABEL: simple_multiple_use:
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; CHECK: .functype simple_multiple_use (i32, i32) -> (){{$}}
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; CHECK-NEXT: i32.mul $push[[NUM0:[0-9]+]]=, $1, $0{{$}}
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; CHECK-NEXT: local.tee $push[[NUM1:[0-9]+]]=, $[[NUM2:[0-9]+]]=, $pop[[NUM0]]{{$}}
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; CHECK-NEXT: call use_a, $pop[[NUM1]]{{$}}
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; CHECK-NEXT: call use_b, $[[NUM2]]{{$}}
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; CHECK-NEXT: return{{$}}
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; NOREGS-LABEL: simple_multiple_use:
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; NOREGS: .functype simple_multiple_use (i32, i32) -> (){{$}}
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; NOREGS-NEXT: local.get 1{{$}}
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; NOREGS-NEXT: local.get 0{{$}}
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; NOREGS-NEXT: i32.mul
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; NOREGS-NEXT: local.tee 0{{$}}
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; NOREGS-NEXT: call use_a{{$}}
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; NOREGS-NEXT: local.get 0{{$}}
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; NOREGS-NEXT: call use_b{{$}}
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; NOREGS-NEXT: return{{$}}
|
|
declare void @use_a(i32)
|
|
declare void @use_b(i32)
|
|
define void @simple_multiple_use(i32 %x, i32 %y) {
|
|
%mul = mul i32 %y, %x
|
|
call void @use_a(i32 %mul)
|
|
call void @use_b(i32 %mul)
|
|
ret void
|
|
}
|
|
|
|
; Multiple uses of the same value in one instruction.
|
|
|
|
; CHECK-LABEL: multiple_uses_in_same_insn:
|
|
; CHECK: .functype multiple_uses_in_same_insn (i32, i32) -> (){{$}}
|
|
; CHECK-NEXT: i32.mul $push[[NUM0:[0-9]+]]=, $1, $0{{$}}
|
|
; CHECK-NEXT: local.tee $push[[NUM1:[0-9]+]]=, $[[NUM2:[0-9]+]]=, $pop[[NUM0]]{{$}}
|
|
; CHECK-NEXT: call use_2, $pop[[NUM1]], $[[NUM2]]{{$}}
|
|
; CHECK-NEXT: return{{$}}
|
|
; NOREGS-LABEL: multiple_uses_in_same_insn:
|
|
; NOREGS: .functype multiple_uses_in_same_insn (i32, i32) -> (){{$}}
|
|
; NOREGS-NEXT: local.get 1{{$}}
|
|
; NOREGS-NEXT: local.get 0{{$}}
|
|
; NOREGS-NEXT: i32.mul
|
|
; NOREGS-NEXT: local.tee 0{{$}}
|
|
; NOREGS-NEXT: local.get 0{{$}}
|
|
; NOREGS-NEXT: call use_2{{$}}
|
|
; NOREGS-NEXT: return{{$}}
|
|
declare void @use_2(i32, i32)
|
|
define void @multiple_uses_in_same_insn(i32 %x, i32 %y) {
|
|
%mul = mul i32 %y, %x
|
|
call void @use_2(i32 %mul, i32 %mul)
|
|
ret void
|
|
}
|
|
|
|
; Commute operands to achieve better stackifying.
|
|
|
|
; CHECK-LABEL: commute:
|
|
; CHECK: .functype commute () -> (i32){{$}}
|
|
; CHECK-NEXT: call $push0=, red{{$}}
|
|
; CHECK-NEXT: call $push1=, green{{$}}
|
|
; CHECK-NEXT: i32.add $push2=, $pop0, $pop1{{$}}
|
|
; CHECK-NEXT: call $push3=, blue{{$}}
|
|
; CHECK-NEXT: i32.add $push4=, $pop2, $pop3{{$}}
|
|
; CHECK-NEXT: return $pop4{{$}}
|
|
; NOREGS-LABEL: commute:
|
|
; NOREGS: .functype commute () -> (i32){{$}}
|
|
; NOREGS-NEXT: call red{{$}}
|
|
; NOREGS-NEXT: call green{{$}}
|
|
; NOREGS-NEXT: i32.add {{$}}
|
|
; NOREGS-NEXT: call blue{{$}}
|
|
; NOREGS-NEXT: i32.add {{$}}
|
|
; NOREGS-NEXT: return{{$}}
|
|
declare i32 @red()
|
|
declare i32 @green()
|
|
declare i32 @blue()
|
|
define i32 @commute() {
|
|
%call = call i32 @red()
|
|
%call1 = call i32 @green()
|
|
%add = add i32 %call1, %call
|
|
%call2 = call i32 @blue()
|
|
%add3 = add i32 %add, %call2
|
|
ret i32 %add3
|
|
}
|
|
|
|
; Don't stackify a register when it would move a the def of the register past
|
|
; an implicit local.get for the register.
|
|
|
|
; CHECK-LABEL: no_stackify_past_use:
|
|
; CHECK: call $1=, callee, $0
|
|
; CHECK-NEXT: i32.const $push0=, 1
|
|
; CHECK-NEXT: i32.add $push1=, $0, $pop0
|
|
; CHECK-NEXT: call $push2=, callee, $pop1
|
|
; CHECK-NEXT: i32.sub $push3=, $pop2, $1
|
|
; CHECK-NEXT: i32.div_s $push4=, $pop3, $1
|
|
; CHECK-NEXT: return $pop4
|
|
; NOREGS-LABEL: no_stackify_past_use:
|
|
; NOREGS: local.get 0{{$}}
|
|
; NOREGS-NEXT: call callee
|
|
; NOREGS-NEXT: local.set 1{{$}}
|
|
; NOREGS-NEXT: local.get 0{{$}}
|
|
; NOREGS-NEXT: i32.const 1
|
|
; NOREGS-NEXT: i32.add
|
|
; NOREGS-NEXT: call callee
|
|
; NOREGS-NEXT: local.get 1{{$}}
|
|
; NOREGS-NEXT: i32.sub
|
|
; NOREGS-NEXT: local.get 1{{$}}
|
|
; NOREGS-NEXT: i32.div_s
|
|
; NOREGS-NEXT: return
|
|
declare i32 @callee(i32)
|
|
define i32 @no_stackify_past_use(i32 %arg) {
|
|
%tmp1 = call i32 @callee(i32 %arg)
|
|
%tmp2 = add i32 %arg, 1
|
|
%tmp3 = call i32 @callee(i32 %tmp2)
|
|
%tmp5 = sub i32 %tmp3, %tmp1
|
|
%tmp6 = sdiv i32 %tmp5, %tmp1
|
|
ret i32 %tmp6
|
|
}
|
|
|
|
; This is the same as no_stackify_past_use, except using a commutative operator,
|
|
; so we can reorder the operands and stackify.
|
|
|
|
; CHECK-LABEL: commute_to_fix_ordering:
|
|
; CHECK: call $push[[L0:.+]]=, callee, $0
|
|
; CHECK: local.tee $push[[L1:.+]]=, $1=, $pop[[L0]]
|
|
; CHECK: i32.const $push0=, 1
|
|
; CHECK: i32.add $push1=, $0, $pop0
|
|
; CHECK: call $push2=, callee, $pop1
|
|
; CHECK: i32.add $push3=, $1, $pop2
|
|
; CHECK: i32.mul $push4=, $pop[[L1]], $pop3
|
|
; CHECK: return $pop4
|
|
; NOREGS-LABEL: commute_to_fix_ordering:
|
|
; NOREGS: local.get 0{{$}}
|
|
; NOREGS: call callee
|
|
; NOREGS: local.tee 1
|
|
; NOREGS: local.get 1{{$}}
|
|
; NOREGS: local.get 0{{$}}
|
|
; NOREGS: i32.const 1
|
|
; NOREGS: i32.add
|
|
; NOREGS: call callee
|
|
; NOREGS: i32.add
|
|
; NOREGS: i32.mul
|
|
; NOREGS: return
|
|
define i32 @commute_to_fix_ordering(i32 %arg) {
|
|
%tmp1 = call i32 @callee(i32 %arg)
|
|
%tmp2 = add i32 %arg, 1
|
|
%tmp3 = call i32 @callee(i32 %tmp2)
|
|
%tmp5 = add i32 %tmp3, %tmp1
|
|
%tmp6 = mul i32 %tmp5, %tmp1
|
|
ret i32 %tmp6
|
|
}
|
|
|
|
; Stackify individual defs of virtual registers with multiple defs.
|
|
|
|
; CHECK-LABEL: multiple_defs:
|
|
; CHECK: f64.add $push[[NUM0:[0-9]+]]=, ${{[0-9]+}}, $pop{{[0-9]+}}{{$}}
|
|
; CHECK-NEXT: local.tee $push[[NUM1:[0-9]+]]=, $[[NUM2:[0-9]+]]=, $pop[[NUM0]]{{$}}
|
|
; CHECK-NEXT: f64.select $push{{[0-9]+}}=, $pop{{[0-9]+}}, $pop[[NUM1]], ${{[0-9]+}}{{$}}
|
|
; CHECK: $[[NUM2]]=,
|
|
; NOREGS-LABEL: multiple_defs:
|
|
; NOREGS: f64.add
|
|
; NOREGS: local.tee
|
|
; NOREGS: f64.select
|
|
define void @multiple_defs(i32 %arg, i32 %arg1, i1 %arg2, i1 %arg3, i1 %arg4) {
|
|
bb:
|
|
br label %bb5
|
|
|
|
bb5: ; preds = %bb21, %bb
|
|
%tmp = phi double [ 0.000000e+00, %bb ], [ %tmp22, %bb21 ]
|
|
%tmp6 = phi double [ 0.000000e+00, %bb ], [ %tmp23, %bb21 ]
|
|
%tmp7 = fcmp olt double %tmp6, 2.323450e+01
|
|
br i1 %tmp7, label %bb8, label %bb21
|
|
|
|
bb8: ; preds = %bb17, %bb5
|
|
%tmp9 = phi double [ %tmp19, %bb17 ], [ %tmp, %bb5 ]
|
|
%tmp10 = fadd double %tmp6, -1.000000e+00
|
|
%tmp11 = select i1 %arg2, double -1.135357e+04, double %tmp10
|
|
%tmp12 = fadd double %tmp11, %tmp9
|
|
br i1 %arg3, label %bb17, label %bb13
|
|
|
|
bb13: ; preds = %bb8
|
|
%tmp14 = or i32 %arg1, 2
|
|
%tmp15 = icmp eq i32 %tmp14, 14
|
|
%tmp16 = select i1 %tmp15, double -1.135357e+04, double 0xBFCE147AE147B000
|
|
br label %bb17
|
|
|
|
bb17: ; preds = %bb13, %bb8
|
|
%tmp18 = phi double [ %tmp16, %bb13 ], [ %tmp10, %bb8 ]
|
|
%tmp19 = fadd double %tmp18, %tmp12
|
|
%tmp20 = fcmp olt double %tmp6, 2.323450e+01
|
|
br i1 %tmp20, label %bb8, label %bb21
|
|
|
|
bb21: ; preds = %bb17, %bb5
|
|
%tmp22 = phi double [ %tmp, %bb5 ], [ %tmp9, %bb17 ]
|
|
%tmp23 = fadd double %tmp6, 1.000000e+00
|
|
br i1 %arg4, label %exit, label %bb5
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Don't move calls past loads
|
|
; CHECK-LABEL: no_stackify_call_past_load:
|
|
; CHECK: call $0=, red
|
|
; CHECK: i32.const $push0=, 0
|
|
; CHECK: i32.load $1=, count($pop0)
|
|
; NOREGS-LABEL: no_stackify_call_past_load:
|
|
; NOREGS: call red
|
|
; NOREGS: i32.const 0
|
|
; NOREGS: i32.load count
|
|
@count = hidden global i32 0, align 4
|
|
define i32 @no_stackify_call_past_load() {
|
|
%a = call i32 @red()
|
|
%b = load i32, i32* @count, align 4
|
|
call i32 @callee(i32 %a)
|
|
ret i32 %b
|
|
; use of a
|
|
}
|
|
|
|
; Don't move stores past loads if there may be aliasing
|
|
; CHECK-LABEL: no_stackify_store_past_load
|
|
; CHECK: i32.store 0($1), $0
|
|
; CHECK: i32.load {{.*}}, 0($2)
|
|
; CHECK: call {{.*}}, callee, $0{{$}}
|
|
; NOREGS-LABEL: no_stackify_store_past_load
|
|
; NOREGS: i32.store 0
|
|
; NOREGS: i32.load 0
|
|
; NOREGS: call callee{{$}}
|
|
define i32 @no_stackify_store_past_load(i32 %a, i32* %p1, i32* %p2) {
|
|
store i32 %a, i32* %p1
|
|
%b = load i32, i32* %p2, align 4
|
|
call i32 @callee(i32 %a)
|
|
ret i32 %b
|
|
}
|
|
|
|
; Can still stackify past invariant loads.
|
|
; CHECK-LABEL: store_past_invar_load
|
|
; CHECK: i32.store 0($1), $0
|
|
; CHECK: call {{.*}}, callee, $0
|
|
; CHECK: i32.load $push{{.*}}, 0($2)
|
|
; CHECK: return $pop
|
|
; NOREGS-LABEL: store_past_invar_load
|
|
; NOREGS: i32.store 0
|
|
; NOREGS: call callee
|
|
; NOREGS: i32.load 0
|
|
; NOREGS: return
|
|
define i32 @store_past_invar_load(i32 %a, i32* %p1, i32* dereferenceable(4) %p2) {
|
|
store i32 %a, i32* %p1
|
|
%b = load i32, i32* %p2, !invariant.load !0
|
|
call i32 @callee(i32 %a)
|
|
ret i32 %b
|
|
}
|
|
|
|
; CHECK-LABEL: ignore_dbg_value:
|
|
; CHECK: .Lfunc_begin
|
|
; CHECK: unreachable
|
|
; NOREGS-LABEL: ignore_dbg_value:
|
|
; NOREGS: .Lfunc_begin
|
|
; NOREGS: unreachable
|
|
declare void @llvm.dbg.value(metadata, i64, metadata, metadata)
|
|
define void @ignore_dbg_value() {
|
|
call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !7, metadata !9), !dbg !10
|
|
unreachable
|
|
}
|
|
|
|
; Don't stackify an expression that might use the stack into a return, since we
|
|
; might insert a prologue before the return.
|
|
|
|
; CHECK-LABEL: no_stackify_past_epilogue:
|
|
; CHECK: return ${{[0-9]+}}{{$}}
|
|
; NOREGS-LABEL: no_stackify_past_epilogue:
|
|
; NOREGS: return{{$}}
|
|
declare i32 @use_memory(i32*)
|
|
define i32 @no_stackify_past_epilogue() {
|
|
%x = alloca i32
|
|
%call = call i32 @use_memory(i32* %x)
|
|
ret i32 %call
|
|
}
|
|
|
|
; Stackify a loop induction variable into a loop comparison.
|
|
|
|
; CHECK-LABEL: stackify_indvar:
|
|
; CHECK: i32.const $push[[L5:.+]]=, 1{{$}}
|
|
; CHECK-NEXT: i32.add $push[[L4:.+]]=, $[[R0:.+]], $pop[[L5]]{{$}}
|
|
; CHECK-NEXT: local.tee $push[[L3:.+]]=, $[[R0]]=, $pop[[L4]]{{$}}
|
|
; CHECK-NEXT: i32.ne $push[[L2:.+]]=, $0, $pop[[L3]]{{$}}
|
|
; NOREGS-LABEL: stackify_indvar:
|
|
; NOREGS: i32.const 1{{$}}
|
|
; NOREGS-NEXT: i32.add
|
|
; NOREGS-NEXT: local.tee 2{{$}}
|
|
; NOREGS-NEXT: i32.ne
|
|
define void @stackify_indvar(i32 %tmp, i32* %v) #0 {
|
|
bb:
|
|
br label %bb3
|
|
|
|
bb3: ; preds = %bb3, %bb2
|
|
%tmp4 = phi i32 [ %tmp7, %bb3 ], [ 0, %bb ]
|
|
%tmp5 = load volatile i32, i32* %v, align 4
|
|
%tmp6 = add nsw i32 %tmp5, %tmp4
|
|
store volatile i32 %tmp6, i32* %v, align 4
|
|
%tmp7 = add nuw nsw i32 %tmp4, 1
|
|
%tmp8 = icmp eq i32 %tmp7, %tmp
|
|
br i1 %tmp8, label %bb10, label %bb3
|
|
|
|
bb10: ; preds = %bb9, %bb
|
|
ret void
|
|
}
|
|
|
|
; Don't stackify a call past a __stack_pointer store.
|
|
|
|
; CHECK-LABEL: stackpointer_dependency:
|
|
; CHECK: call {{.+}}, stackpointer_callee,
|
|
; CHECK-NEXT: global.set __stack_pointer,
|
|
; NOREGS-LABEL: stackpointer_dependency:
|
|
; NOREGS: call stackpointer_callee
|
|
; NOREGS: global.set __stack_pointer
|
|
declare i32 @stackpointer_callee(i8* readnone, i8* readnone) nounwind readnone
|
|
declare i8* @llvm.frameaddress(i32)
|
|
define i32 @stackpointer_dependency(i8* readnone) {
|
|
%2 = tail call i8* @llvm.frameaddress(i32 0)
|
|
%3 = tail call i32 @stackpointer_callee(i8* %0, i8* %2)
|
|
ret i32 %3
|
|
}
|
|
|
|
; Stackify a call_indirect with respect to its ordering
|
|
|
|
; CHECK-LABEL: call_indirect_stackify:
|
|
; CHECK: i32.load $push[[L4:.+]]=, 0($0)
|
|
; CHECK-NEXT: local.tee $push[[L3:.+]]=, $0=, $pop[[L4]]
|
|
; CHECK-NEXT: i32.load $push[[L0:.+]]=, 0($0)
|
|
; CHECK-NEXT: i32.load $push[[L1:.+]]=, 0($pop[[L0]])
|
|
; CHECK-NEXT: call_indirect $push{{.+}}=, $pop[[L3]], $1, $pop[[L1]]
|
|
; NOREGS-LABEL: call_indirect_stackify:
|
|
; NOREGS: i32.load 0
|
|
; NOREGS-NEXT: local.tee 0
|
|
; NOREGS: i32.load 0
|
|
; NOREGS-NEXT: i32.load 0
|
|
; NOREGS-NEXT: call_indirect (i32, i32) -> (i32)
|
|
%class.call_indirect = type { i32 (...)** }
|
|
define i32 @call_indirect_stackify(%class.call_indirect** %objptr, i32 %arg) {
|
|
%obj = load %class.call_indirect*, %class.call_indirect** %objptr
|
|
%addr = bitcast %class.call_indirect* %obj to i32(%class.call_indirect*, i32)***
|
|
%vtable = load i32(%class.call_indirect*, i32)**, i32(%class.call_indirect*, i32)*** %addr
|
|
%vfn = getelementptr inbounds i32(%class.call_indirect*, i32)*, i32(%class.call_indirect*, i32)** %vtable, i32 0
|
|
%f = load i32(%class.call_indirect*, i32)*, i32(%class.call_indirect*, i32)** %vfn
|
|
%ret = call i32 %f(%class.call_indirect* %obj, i32 %arg)
|
|
ret i32 %ret
|
|
}
|
|
|
|
!llvm.module.flags = !{!0}
|
|
!llvm.dbg.cu = !{!1}
|
|
|
|
!0 = !{i32 2, !"Debug Info Version", i32 3}
|
|
!1 = distinct !DICompileUnit(language: DW_LANG_C99, file: !2, producer: "clang version 3.9.0 (trunk 266005) (llvm/trunk 266105)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !3)
|
|
!2 = !DIFile(filename: "test.c", directory: "/")
|
|
!3 = !{}
|
|
!5 = distinct !DISubprogram(name: "test", scope: !2, file: !2, line: 10, type: !6, isLocal: false, isDefinition: true, scopeLine: 11, flags: DIFlagPrototyped, isOptimized: true, unit: !1, retainedNodes: !3)
|
|
!6 = !DISubroutineType(types: !3)
|
|
!7 = !DILocalVariable(name: "nzcnt", scope: !5, file: !2, line: 15, type: !8)
|
|
!8 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
|
|
!9 = !DIExpression()
|
|
!10 = !DILocation(line: 15, column: 6, scope: !5)
|