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Inliner section safety #3

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1 change: 1 addition & 0 deletions llvm/include/llvm/IR/Attributes.td
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Original file line number Diff line number Diff line change
Expand Up @@ -455,6 +455,7 @@ def : CompatRule<"isEqual<UseSampleProfileAttr>">;
def : CompatRule<"isEqual<NoProfileAttr>">;
def : CompatRule<"checkDenormMode">;
def : CompatRule<"checkStrictFP">;
def : CompatRule<"checkSectionsMSVC">;
def : CompatRuleStrAttr<"isEqual", "sign-return-address">;
def : CompatRuleStrAttr<"isEqual", "sign-return-address-key">;
def : CompatRuleStrAttr<"isEqual", "branch-protection-pauth-lr">;
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42 changes: 42 additions & 0 deletions llvm/lib/IR/Attributes.cpp
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Expand Up @@ -2508,6 +2508,48 @@ static bool checkStrictFP(const Function &Caller, const Function &Callee) {
Caller.getAttributes().hasFnAttr(Attribute::StrictFP);
}

static bool checkSectionsMSVC(const Function &Caller, const Function &Callee) {
// Apply inlining section compatibility test only to MSVC environment
if (!Caller.getParent()->getTargetTriple().isWindowsMSVCEnvironment())
return true;

StringRef CallerSection = Caller.getSection();
StringRef CalleeSection = Callee.getSection();

// Sections match, inlining ok
if (!CallerSection.compare(CalleeSection))
return true;

bool isCallerPaged = CallerSection.starts_with("PAGE");
bool isCalleePaged = CalleeSection.starts_with("PAGE");

// Paged caller & callee
if (isCallerPaged && isCalleePaged) {
// Compare section names up to '$' separator if present
size_t CallerComparable = CallerSection.size();
size_t CalleeComparable = CalleeSection.size();
size_t CallerSep = CallerSection.find('$');
size_t CalleeSep = CalleeSection.find('$');

if (CallerSep != StringRef::npos)
CallerComparable = CallerSep;
if (CalleeSep != StringRef::npos)
CalleeComparable = CalleeSep;
if (CallerComparable != CalleeComparable)
return false;

StringRef CallerComparableSection =
CallerSection.substr(0, CallerComparable);
StringRef CalleeComparableSection =
CalleeSection.substr(0, CallerComparable);
return !CallerComparableSection.compare(CalleeComparableSection);
} else if (isCalleePaged || isCallerPaged)
// Paged and unpaged code must not be mixed
return false;

return true;
}

template<typename AttrClass>
static bool isEqual(const Function &Caller, const Function &Callee) {
return Caller.getFnAttribute(AttrClass::getKind()) ==
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157 changes: 157 additions & 0 deletions llvm/test/Transforms/Inline/inline-msvc-sections.ll
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@@ -0,0 +1,157 @@
; RUN: opt < %s -passes=inline -inline-threshold=100 -S | FileCheck %s
; RUN: opt < %s -passes='cgscc(inline)' -inline-threshold=100 -S | FileCheck %s
; RUN: opt < %s -mtriple=aarch64-windows-msvc -passes=inline -inline-threshold=100 -S | FileCheck %s -check-prefix=MSVC
; RUN: opt < %s -mtriple=aarch64-windows-msvc -passes='cgscc(inline)' -inline-threshold=100 -S | FileCheck %s -check-prefix=MSVC

define i32 @nosection_callee(i32 %x) {
%x1 = add i32 %x, 1
%x2 = add i32 %x1, 1
%x3 = add i32 %x2, 1
call void @extern()
ret i32 %x3
}

define i32 @section_callee(i32 %x) section "FOO" {
%x1 = add i32 %x, 1
%x2 = add i32 %x1, 1
%x3 = add i32 %x2, 1
call void @extern()
ret i32 %x3
}

define i32 @sectionpostfix_callee(i32 %x) section "FOO$BBBB" {
%x1 = add i32 %x, 1
%x2 = add i32 %x1, 1
%x3 = add i32 %x2, 1
call void @extern()
ret i32 %x3
}

define i32 @paged_callee(i32 %x) section "PAGE" {
%x1 = add i32 %x, 1
%x2 = add i32 %x1, 1
%x3 = add i32 %x2, 1
call void @extern()
ret i32 %x3
}

define i32 @pagedpostfix_callee(i32 %x) section "PAGE$aaa" {
%x1 = add i32 %x, 1
%x2 = add i32 %x1, 1
%x3 = add i32 %x2, 1
call void @extern()
ret i32 %x3
}

define i32 @nosection_caller(i32 %y1) {
%y2 = call i32 @nosection_callee(i32 %y1)
%y3 = call i32 @section_callee(i32 %y2)
%y4 = call i32 @sectionpostfix_callee(i32 %y3)
%y5 = call i32 @paged_callee(i32 %y4)
%y6 = call i32 @pagedpostfix_callee(i32 %y5)
ret i32 %y6
}

; CHECK-LABEL: @nosection_caller
; CHECK-NOT: @nosection_callee
; CHECK-NOT: @section_callee
; CHECK-NOT: @sectionpostfix_callee
; CHECK-NOT: @paged_callee
; CHECK-NOT: @pagedpostfix_callee
; MSVC-LABEL: @nosection_caller
; MSVC-NOT: @nosection_callee
; MSVC-NOT: @section_callee
; MSVC-NOT: @sectionpostfix_callee
; MSVC: @paged_callee
; MSVC: @pagedpostfix_callee

define i32 @section_caller(i32 %y1) section "FOO" {
%y2 = call i32 @nosection_callee(i32 %y1)
%y3 = call i32 @section_callee(i32 %y2)
%y4 = call i32 @sectionpostfix_callee(i32 %y3)
%y5 = call i32 @paged_callee(i32 %y4)
%y6 = call i32 @pagedpostfix_callee(i32 %y5)
ret i32 %y6
}

; CHECK-LABEL: @section_caller
; CHECK-NOT: @nosection_callee
; CHECK-NOT: @section_callee
; CHECK-NOT: @sectionpostfix_callee
; CHECK-NOT: @paged_callee
; CHECK-NOT: @pagedpostfix_callee
; MSVC-LABEL: @section_caller
; MSVC-NOT: @nosection_callee
; MSVC-NOT: @section_callee
; MSVC-NOT: @sectionpostfix_callee
; MSVC: @paged_callee
; MSVC: @pagedpostfix_callee

define i32 @sectionpostfix_caller(i32 %y1) section "FOO$ZZZ" {
%y2 = call i32 @nosection_callee(i32 %y1)
%y3 = call i32 @section_callee(i32 %y2)
%y4 = call i32 @sectionpostfix_callee(i32 %y3)
%y5 = call i32 @paged_callee(i32 %y4)
%y6 = call i32 @pagedpostfix_callee(i32 %y5)
ret i32 %y6
}

; CHECK-LABEL: @sectionpostfix_caller
; CHECK-NOT: @nosection_callee
; CHECK-NOT: @section_callee
; CHECK-NOT: @sectionpostfix_callee
; CHECK-NOT: @paged_callee
; CHECK-NOT: @pagedpostfix_callee
; MSVC-LABEL: @sectionpostfix_caller
; MSVC-NOT: @nosection_callee
; MSVC-NOT: @section_callee
; MSVC-NOT: @sectionpostfix_callee
; MSVC: @paged_callee
; MSVC: @pagedpostfix_callee

define i32 @paged_caller(i32 %y1) section "PAGE" {
%y2 = call i32 @nosection_callee(i32 %y1)
%y3 = call i32 @section_callee(i32 %y2)
%y4 = call i32 @sectionpostfix_callee(i32 %y3)
%y5 = call i32 @paged_callee(i32 %y4)
%y6 = call i32 @pagedpostfix_callee(i32 %y5)
ret i32 %y6
}

; CHECK-LABEL: @paged_caller
; CHECK-NOT: @nosection_callee
; CHECK-NOT: @section_callee
; CHECK-NOT: @sectionpostfix_callee
; CHECK-NOT: @paged_callee
; CHECK-NOT: @pagedpostfix_callee
; MSVC-LABEL: @paged_caller
; MSVC: @nosection_callee
; MSVC: @section_callee
; MSVC: @sectionpostfix_callee
; MSVC-NOT: @paged_callee
; MSVC-NOT: @pagedpostfix_callee

define i32 @pagedpostfix_caller(i32 %y1) section "PAGE$ZZZ" {
%y2 = call i32 @nosection_callee(i32 %y1)
%y3 = call i32 @section_callee(i32 %y2)
%y4 = call i32 @sectionpostfix_callee(i32 %y3)
%y5 = call i32 @paged_callee(i32 %y4)
%y6 = call i32 @pagedpostfix_callee(i32 %y5)
ret i32 %y6
}

; CHECK-LABEL: @pagedpostfix_caller
; CHECK-NOT: @nosection_callee
; CHECK-NOT: @section_callee
; CHECK-NOT: @sectionpostfix_callee
; CHECK-NOT: @paged_callee
; CHECK-NOT: @pagedpostfix_callee
; MSVC-LABEL: @pagedpostfix_caller
; MSVC: @nosection_callee
; MSVC: @section_callee
; MSVC: @sectionpostfix_callee
; MSVC-NOT: @paged_callee
; MSVC-NOT: @pagedpostfix_callee

declare void @extern()