llvm · aeubanks · Apr 11, 2024 · Apr 7, 2024 · Apr 8, 2024
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -2627,7 +2627,7 @@ void CodeGenModule::setNonAliasAttributes(GlobalDecl GD,
         addUsedGlobal(F);
       if (auto *SA = D->getAttr<PragmaClangTextSectionAttr>())
         if (!D->getAttr<SectionAttr>())
-          F->addFnAttr("implicit-section-name", SA->getName());
+          F->setSection(SA->getName());
 
       llvm::AttrBuilder Attrs(F->getContext());
       if (GetCPUAndFeaturesAttributes(GD, Attrs)) {

diff --git a/clang/test/CodeGen/clang-sections-attribute.c b/clang/test/CodeGen/clang-sections-attribute.c
@@ -69,8 +69,5 @@ static int int_zvar;
 // CHECK: define internal void @int_fun() #0 section ".int_fun_attr"
 // CHECK: define internal void @int_fun2() #0 section ".int_fun2_attr"
 //
-// Function attributes should not include implicit-section-name.
-// CHECK-NOT: attributes #0 = {{.*}}implicit-section-name
-//
 // No other attribute group should be present in the file.
 // CHECK-NOT: attributes #1
diff --git a/clang/test/CodeGenCXX/clang-sections.cpp b/clang/test/CodeGenCXX/clang-sections.cpp
@@ -81,24 +81,22 @@ int hoo(void) {
 //CHECK: @p ={{.*}} constant i32 7, align 4
 //CHECK: @_ZL5fptrs = internal constant [2 x ptr] [ptr @foo, ptr @goo], align {{4|8}} #3
 
-//CHECK: define{{.*}} i32 @foo() #5 {
-//CHECK: define{{.*}} i32 @goo() #6 {
-//CHECK: declare i32 @zoo(ptr noundef, ptr noundef) #7
-//CHECK: define{{.*}} i32 @hoo() #8 {
+//ELF: define{{.*}} i32 @foo(){{.*}} section "my_text.1" {
+//ELF: define{{.*}} i32 @goo(){{.*}} section "my_text.2" {
+//MACHO: define{{.*}} i32 @foo(){{.*}} section "__TEXT,__mytext1" {
+//MACHO: define{{.*}} i32 @goo(){{.*}} section "__TEXT,__mytext2" {
+
+// ensure zoo/hoo don't have a section
+//CHECK: declare i32 @zoo(ptr noundef, ptr noundef) #6{{$}}
+//CHECK: define{{.*}} i32 @hoo() #5 {
 
 //ELF: attributes #0 = { "bss-section"="my_bss.1" "data-section"="my_data.1" "rodata-section"="my_rodata.1" }
 //ELF: attributes #1 = { "data-section"="my_data.1" "rodata-section"="my_rodata.1" }
 //ELF: attributes #2 = { "bss-section"="my_bss.2" "rodata-section"="my_rodata.1" }
 //ELF: attributes #3 = { "bss-section"="my_bss.2" "data-section"="my_data.2" "relro-section"="my_relro.2" "rodata-section"="my_rodata.2" }
 //ELF: attributes #4 = { "relro-section"="my_relro.2" }
-//ELF: attributes #5 = { {{.*"implicit-section-name"="my_text.1".*}} }
-//ELF: attributes #6 = { {{.*"implicit-section-name"="my_text.2".*}} }
 //MACHO: attributes #0 = { "bss-section"="__BSS,__mybss1" "data-section"="__DATA,__mydata1" "rodata-section"="__RODATA,__myrodata1" }
 //MACHO: attributes #1 = { "data-section"="__DATA,__mydata1" "rodata-section"="__RODATA,__myrodata1" }
 //MACHO: attributes #2 = { "bss-section"="__BSS,__mybss2" "rodata-section"="__RODATA,__myrodata1" }
 //MACHO: attributes #3 = { "bss-section"="__BSS,__mybss2" "data-section"="__DATA,__mydata2" "relro-section"="__RELRO,__myrelro2" "rodata-section"="__RODATA,__myrodata2" }
 //MACHO: attributes #4 = { "relro-section"="__RELRO,__myrelro2" }
-//MACHO: attributes #5 = { {{.*"implicit-section-name"="__TEXT,__mytext1".*}} }
-//MACHO: attributes #6 = { {{.*"implicit-section-name"="__TEXT,__mytext2".*}} }
-//CHECK-NOT: attributes #7 = { {{.*"implicit-section-name".*}} }
-//CHECK-NOT: attributes #8 = { {{.*"implicit-section-name".*}} }
diff --git a/llvm/lib/CodeGen/TargetInstrInfo.cpp b/llvm/lib/CodeGen/TargetInstrInfo.cpp
@@ -1470,8 +1470,7 @@ bool TargetInstrInfo::isFunctionSafeToSplit(const MachineFunction &MF) const {
   // since the split part may not be placed in a contiguous region. It may also
   // be more beneficial to augment the linker to ensure contiguous layout of
   // split functions within the same section as specified by the attribute.
-  if (MF.getFunction().hasSection() ||
-      MF.getFunction().hasFnAttribute("implicit-section-name"))
+  if (MF.getFunction().hasSection())
     return false;
 
   // We don't want to proceed further for cold functions

diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -797,10 +797,6 @@ static MCSection *selectExplicitSectionGlobal(
       SectionName = Attrs.getAttribute("data-section").getValueAsString();
     }
   }
-  const Function *F = dyn_cast<Function>(GO);
-  if (F && F->hasFnAttribute("implicit-section-name")) {
-    SectionName = F->getFnAttribute("implicit-section-name").getValueAsString();
-  }
 
   // Infer section flags from the section name if we can.
   Kind = getELFKindForNamedSection(SectionName, Kind);
@@ -934,7 +930,7 @@ MCSection *TargetLoweringObjectFileELF::getUniqueSectionForFunction(
   unsigned Flags = getELFSectionFlags(Kind);
   // If the function's section names is pre-determined via pragma or a
   // section attribute, call selectExplicitSectionGlobal.
-  if (F.hasSection() || F.hasFnAttribute("implicit-section-name"))
+  if (F.hasSection())
     return selectExplicitSectionGlobal(
         &F, Kind, TM, getContext(), getMangler(), NextUniqueID,
         Used.count(&F), /* ForceUnique = */true);
@@ -1298,11 +1294,6 @@ MCSection *TargetLoweringObjectFileMachO::getExplicitSectionGlobal(
     }
   }
 
-  const Function *F = dyn_cast<Function>(GO);
-  if (F && F->hasFnAttribute("implicit-section-name")) {
-    SectionName = F->getFnAttribute("implicit-section-name").getValueAsString();
-  }
-
   // Parse the section specifier and create it if valid.
   StringRef Segment, Section;
   unsigned TAA = 0, StubSize = 0;

diff --git a/llvm/lib/IR/AutoUpgrade.cpp b/llvm/lib/IR/AutoUpgrade.cpp
@@ -5267,6 +5267,14 @@ void llvm::UpgradeFunctionAttributes(Function &F) {
   F.removeRetAttrs(AttributeFuncs::typeIncompatible(F.getReturnType()));
   for (auto &Arg : F.args())
     Arg.removeAttrs(AttributeFuncs::typeIncompatible(Arg.getType()));
+
+  // Older versions of LLVM treated an "implicit-section-name" attribute
+  // similarly to directly setting the section on a Function.
+  if (Attribute A = F.getFnAttribute("implicit-section-name");
+      A.isValid() && A.isStringAttribute()) {
+    F.setSection(A.getValueAsString());
+    F.removeFnAttr("implicit-section-name");
+  }
 }
 
 static bool isOldLoopArgument(Metadata *MD) {

diff --git a/llvm/lib/Target/TargetLoweringObjectFile.cpp b/llvm/lib/Target/TargetLoweringObjectFile.cpp
@@ -334,11 +334,6 @@ MCSection *TargetLoweringObjectFile::SectionForGlobal(
     }
   }
 
-  if (auto *F = dyn_cast<Function>(GO)) {
-    if (F->hasFnAttribute("implicit-section-name"))
-      return getExplicitSectionGlobal(GO, Kind, TM);
-  }
-
   // Use default section depending on the 'type' of global
   return SelectSectionForGlobal(GO, Kind, TM);
 }

diff --git a/llvm/test/Bitcode/upgrade-implicit-section-name.ll b/llvm/test/Bitcode/upgrade-implicit-section-name.ll
@@ -0,0 +1,8 @@
+; RUN: llvm-as < %s | llvm-dis - | FileCheck %s
+
+; CHECK: define void @f() section "foo_section"
+; CHECK-NOT: "implicit-section-name"
+
+define void @f() "implicit-section-name"="foo_section" {
+  ret void
+}
diff --git a/llvm/test/CodeGen/AArch64/clang-section-macho.ll b/llvm/test/CodeGen/AArch64/clang-section-macho.ll
diff --git a/llvm/test/CodeGen/ARM/clang-section.ll b/llvm/test/CodeGen/ARM/clang-section.ll
@@ -22,20 +22,6 @@ target triple = "armv7-arm-none-eabi"
 @o = global i32 6, align 4
 @p = constant i32 7, align 4
 
-; Function Attrs: noinline nounwind
-define i32 @foo() #4 {
-entry:
-  %0 = load i32, ptr @b, align 4
-  ret i32 %0
-}
-
-; Function Attrs: noinline
-define i32 @goo() #5 {
-entry:
-  %call = call i32 @zoo(ptr @_ZL1g, ptr @_ZZ3gooE7lstat_h)
-  ret i32 %call
-}
-
 declare i32 @zoo(ptr, ptr) #6
 
 ; Function Attrs: noinline nounwind
@@ -49,8 +35,6 @@ attributes #0 = { "bss-section"="my_bss.1" "data-section"="my_data.1" "rodata-se
 attributes #1 = { "data-section"="my_data.1" "rodata-section"="my_rodata.1" }
 attributes #2 = { "bss-section"="my_bss.2" "rodata-section"="my_rodata.1" }
 attributes #3 = { "bss-section"="my_bss.2" "data-section"="my_data.2" "rodata-section"="my_rodata.2" }
-attributes #4 = { noinline nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "denormal-fp-math"="preserve-sign,preserve-sign" "disable-tail-calls"="false" "implicit-section-name"="my_text.1" "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="true" "no-jump-tables"="false" "no-nans-fp-math"="true" "no-signed-zeros-fp-math"="true" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="cortex-a9" "target-features"="+dsp,+fp16,+neon,+vfp3" "unsafe-fp-math"="false" "use-soft-float"="false" }
-attributes #5 = { noinline "correctly-rounded-divide-sqrt-fp-math"="false" "denormal-fp-math"="preserve-sign,preserve-sign" "disable-tail-calls"="false" "implicit-section-name"="my_text.2" "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="true" "no-jump-tables"="false" "no-nans-fp-math"="true" "no-signed-zeros-fp-math"="true" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="cortex-a9" "target-features"="+dsp,+fp16,+neon,+vfp3" "unsafe-fp-math"="false" "use-soft-float"="false" }
 attributes #6 = { "correctly-rounded-divide-sqrt-fp-math"="false" "denormal-fp-math"="preserve-sign,preserve-sign" "disable-tail-calls"="false" "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="true" "no-nans-fp-math"="true" "no-signed-zeros-fp-math"="true" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="cortex-a9" "target-features"="+dsp,+fp16,+neon,+vfp3" "unsafe-fp-math"="false" "use-soft-float"="false" }
 attributes #7 = { noinline nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "denormal-fp-math"="preserve-sign,preserve-sign" "disable-tail-calls"="false" "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="true" "no-jump-tables"="false" "no-nans-fp-math"="true" "no-signed-zeros-fp-math"="true" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="cortex-a9" "target-features"="+dsp,+fp16,+neon,+vfp3" "unsafe-fp-math"="false" "use-soft-float"="false" }
 
@@ -61,14 +45,6 @@ attributes #7 = { noinline nounwind "correctly-rounded-divide-sqrt-fp-math"="fal
 !2 = !{i32 1, !"enumsize_buildattr", i32 2}
 !3 = !{i32 1, !"armlib_unavailable", i32 0}
 
-;CHECK: 	.section	my_text.1,"ax",%progbits
-;CHECK: 	.type	foo,%function
-;CHECK: foo:
-
-;CHECK: 	.section	my_text.2,"ax",%progbits
-;CHECK: 	.type	goo,%function
-;CHECK: goo:
-
 ;CHECK: 	.text
 ;CHECK: 	.type	hoo,%function
 ;CHECK: hoo:

diff --git a/llvm/test/CodeGen/Generic/machine-function-splitter.ll b/llvm/test/CodeGen/Generic/machine-function-splitter.ll
@@ -260,25 +260,6 @@ exit:
   ret i32 %5
 }
 
-define void @foo9(i1 zeroext %0) nounwind #0 !prof !14 {
-;; Check that function with section attribute is not split.
-; MFS-DEFAULTS-LABEL: foo9
-; MFS-DEFAULTS-NOT:   foo9.cold:
-  br i1 %0, label %2, label %4, !prof !17
-
-2:                                                ; preds = %1
-  %3 = call i32 @bar()
-  br label %6
-
-4:                                                ; preds = %1
-  %5 = call i32 @baz()
-  br label %6
-
-6:                                                ; preds = %4, %2
-  %7 = tail call i32 @qux()
-  ret void
-}
-
 define i32 @foo10(i1 zeroext %0) personality ptr @__gxx_personality_v0 !prof !14 {
 ;; Check that nop is inserted just before the EH pad if it's beginning a section.
 ; MFS-DEFAULTS-LABEL:         foo10
@@ -564,10 +545,10 @@ define i32 @foo19(i32 %in) !prof !14 !section_prefix !15 {
 ; MFS-DEFAULTS-LABEL:        foo19
 ; MFS-DEFAULTS:              .section        .text.split.foo19
 ; MFS-DEFAULTS-NEXT:         foo19.cold:
-; MFS-DEFAULTS-X86:            .LJTI18_0
-; MFS-DEFAULTS-AARCH64-NOT:    .LJTI18_0
+; MFS-DEFAULTS-X86:            .LJTI17_0
+; MFS-DEFAULTS-AARCH64-NOT:    .LJTI17_0
 ; MFS-DEFAULTS:              .section        .rodata
-; MFS-DEFAULTS:                .LJTI18_0
+; MFS-DEFAULTS:                .LJTI17_0
   %cmp = icmp sgt i32 %in, 3
   br i1 %cmp, label %hot, label %cold_switch, !prof !17
 
@@ -638,8 +619,6 @@ declare i32 @__gxx_personality_v0(...)
 
 @_ZTIi = external constant ptr
 
-attributes #0 = { "implicit-section-name"="nosplit" }
-
 !llvm.module.flags = !{!0}
 !0 = !{i32 1, !"ProfileSummary", !1}
 !1 = !{!2, !3, !4, !5, !6, !7, !8, !9}

diff --git a/llvm/test/CodeGen/X86/basic-block-sections-pragma-sections.ll b/llvm/test/CodeGen/X86/basic-block-sections-pragma-sections.ll
@@ -38,7 +38,7 @@
 ;;   return 0;
 ;; }
 
-define dso_local i32 @_Z3fooi(i32 %n) local_unnamed_addr #0 {
+define dso_local i32 @_Z3fooi(i32 %n) local_unnamed_addr section "foo_section" {
 entry:
   %cmp = icmp slt i32 %n, 0
   br i1 %cmp, label %if.then, label %if.end
@@ -52,5 +52,3 @@ if.end:                                           ; preds = %entry
 }
 
 declare dso_local void @exit(i32) local_unnamed_addr
-
-attributes #0 = {"implicit-section-name"="foo_section" }