[RISCV] Don't outline pcrel_lo when the function has a section prefix (#107943)

GNU ld will error when encountering a pcrel_lo whose corresponding
pcrel_hi is in a different section. [1] introduced a check to help
prevent this issue by preventing outlining in a few circumstances.
However, we can also hit this same issue when outlining from functions
with prefixes ("hot"/"unlikely"/"unknown" from profile information, for
example) as the outlined function might not have the same prefix,
possibly resulting in a "paired" pcrel_lo and pcrel_hi ending up in
different sections.

To prevent this issue, take a similar approach as [1] and additionally
prevent outlining when we see a pcrel_lo and the function has a prefix.

[1]
96c85f80f0

Fixes #107520

(cherry picked from commit 866b93e6b33fac9a4bc62bbc32199bd98f434784)
This commit is contained in:
Jonathon Penix 2024-09-11 09:53:11 -07:00 committed by Tobias Hieta
parent 6278084bc6
commit a847b66a75
2 changed files with 99 additions and 7 deletions

View File

@ -2902,7 +2902,7 @@ RISCVInstrInfo::getOutliningTypeImpl(MachineBasicBlock::iterator &MBBI,
// if any possible.
if (MO.getTargetFlags() == RISCVII::MO_PCREL_LO &&
(MI.getMF()->getTarget().getFunctionSections() || F.hasComdat() ||
F.hasSection()))
F.hasSection() || F.getSectionPrefix()))
return outliner::InstrType::Illegal;
}

View File

@ -18,6 +18,9 @@
define i32 @foo2(i32 %a, i32 %b) comdat { ret i32 0 }
define i32 @foo3(i32 %a, i32 %b) section ".abc" { ret i32 0 }
define i32 @foo4(i32 %a, i32 %b) !section_prefix !0 { ret i32 0 }
!0 = !{!"function_section_prefix", !"myprefix"}
...
---
name: foo
@ -27,23 +30,24 @@ body: |
; CHECK: bb.0:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11, implicit $x13
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_1, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11, implicit $x13
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11, implicit $x13
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_1, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11, implicit $x13
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11, implicit $x13
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_1, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11, implicit $x13
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: PseudoRET
;
; CHECK-FS-LABEL: name: foo
; CHECK-FS: bb.0:
; CHECK-FS-NEXT: liveins: $x10, $x11, $x13
@ -109,26 +113,27 @@ body: |
; CHECK: bb.0:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_1, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_1, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_1, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: PseudoRET
;
; CHECK-FS-LABEL: name: foo2
; CHECK-FS: bb.0:
; CHECK-FS-NEXT: liveins: $x10, $x11, $x13
@ -223,6 +228,7 @@ body: |
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: PseudoRET
;
; CHECK-FS-LABEL: name: foo3
; CHECK-FS: bb.0:
; CHECK-FS-NEXT: liveins: $x10, $x11, $x13
@ -289,3 +295,89 @@ body: |
bb.3:
PseudoRET
...
---
name: foo4
tracksRegLiveness: true
body: |
; CHECK-LABEL: name: foo4
; CHECK: bb.0:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.2:
; CHECK-NEXT: liveins: $x10, $x11, $x13
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-NEXT: PseudoBR %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: PseudoRET
;
; CHECK-FS-LABEL: name: foo4
; CHECK-FS: bb.0:
; CHECK-FS-NEXT: liveins: $x10, $x11, $x13
; CHECK-FS-NEXT: {{ $}}
; CHECK-FS-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-FS-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-FS-NEXT: PseudoBR %bb.3
; CHECK-FS-NEXT: {{ $}}
; CHECK-FS-NEXT: bb.1:
; CHECK-FS-NEXT: liveins: $x10, $x11, $x13
; CHECK-FS-NEXT: {{ $}}
; CHECK-FS-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-FS-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-FS-NEXT: PseudoBR %bb.3
; CHECK-FS-NEXT: {{ $}}
; CHECK-FS-NEXT: bb.2:
; CHECK-FS-NEXT: liveins: $x10, $x11, $x13
; CHECK-FS-NEXT: {{ $}}
; CHECK-FS-NEXT: $x5 = PseudoCALLReg target-flags(riscv-call) @OUTLINED_FUNCTION_0, implicit-def $x5, implicit-def $x10, implicit-def $x11, implicit-def $x12, implicit $x10, implicit $x11
; CHECK-FS-NEXT: $x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
; CHECK-FS-NEXT: PseudoBR %bb.3
; CHECK-FS-NEXT: {{ $}}
; CHECK-FS-NEXT: bb.3:
; CHECK-FS-NEXT: PseudoRET
bb.0:
liveins: $x10, $x11, $x13
$x11 = ORI $x11, 1023
$x12 = ADDI $x10, 17
$x11 = AND $x12, $x11
$x10 = SUB $x10, $x11
$x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
PseudoBR %bb.3
bb.1:
liveins: $x10, $x11, $x13
$x11 = ORI $x11, 1023
$x12 = ADDI $x10, 17
$x11 = AND $x12, $x11
$x10 = SUB $x10, $x11
$x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
PseudoBR %bb.3
bb.2:
liveins: $x10, $x11, $x13
$x11 = ORI $x11, 1023
$x12 = ADDI $x10, 17
$x11 = AND $x12, $x11
$x10 = SUB $x10, $x11
$x11 = LW killed renamable $x13, target-flags(riscv-pcrel-lo) <mcsymbol .Lpcrel_hi1> :: (dereferenceable load (s32) from @bar)
PseudoBR %bb.3
bb.3:
PseudoRET
...