From 36f31617d3b64da3965f0d2d5173e03beece5de5 Mon Sep 17 00:00:00 2001 From: Stefan Pintilie Date: Fri, 24 Aug 2018 15:51:47 +0000 Subject: [PATCH] [Exception Handling] Unwind tables are required for all functions that have an EH personality. This patch is for defect: https://bugs.llvm.org/show_bug.cgi?id=32611 Functions may require unwind tables even if they are marked with the attribute nounwind. Any function with an EH personality may require an unwind table. Differential Revision: https://reviews.llvm.org/D50987 llvm-svn: 340614 --- llvm/include/llvm/IR/Function.h | 2 +- llvm/test/CodeGen/PowerPC/uwtables.ll | 51 +++++++++++++++++++++++++ llvm/test/CodeGen/X86/uwtables.ll | 43 +++++++++++++++++++++ llvm/test/CodeGen/X86/x86-shrink-wrap-unwind.ll | 1 + 4 files changed, 96 insertions(+), 1 deletion(-) create mode 100644 llvm/test/CodeGen/PowerPC/uwtables.ll create mode 100644 llvm/test/CodeGen/X86/uwtables.ll diff --git a/llvm/include/llvm/IR/Function.h b/llvm/include/llvm/IR/Function.h index 6362976..1b91537 100644 --- a/llvm/include/llvm/IR/Function.h +++ b/llvm/include/llvm/IR/Function.h @@ -571,7 +571,7 @@ public: /// True if this function needs an unwind table. bool needsUnwindTableEntry() const { - return hasUWTable() || !doesNotThrow(); + return hasUWTable() || !doesNotThrow() || hasPersonalityFn(); } /// Determine if the function returns a structure through first diff --git a/llvm/test/CodeGen/PowerPC/uwtables.ll b/llvm/test/CodeGen/PowerPC/uwtables.ll new file mode 100644 index 0000000..1968b71 --- /dev/null +++ b/llvm/test/CodeGen/PowerPC/uwtables.ll @@ -0,0 +1,51 @@ +; RUN: llc -mcpu=pwr9 -mtriple=powerpc64le-unknown-unknown \ +; RUN: -verify-machineinstrs -ppc-asm-full-reg-names \ +; RUN: -ppc-vsr-nums-as-vr < %s | FileCheck %s +; RUN: llc -mcpu=pwr8 -mtriple=powerpc64le-unknown-unknown \ +; RUN: -verify-machineinstrs -ppc-asm-full-reg-names \ +; RUN: -ppc-vsr-nums-as-vr < %s | FileCheck %s +; RUN: llc -mtriple=powerpc64-unknown-unknown \ +; RUN: -verify-machineinstrs -ppc-asm-full-reg-names \ +; RUN: -ppc-vsr-nums-as-vr < %s | FileCheck %s + + +@_ZTIi = external constant i8* + +; Function is marked as nounwind but it still throws with __cxa_throw and +; calls __cxa_call_unexpected. +; Need to make sure that we do not only have a debug frame. +; Function Attrs: noreturn nounwind +define void @_Z4funcv() local_unnamed_addr #0 personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) { +entry: + %exception = tail call i8* @__cxa_allocate_exception(i64 4) + %0 = bitcast i8* %exception to i32* + store i32 100, i32* %0, align 16 + invoke void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) + to label %unreachable unwind label %lpad + +lpad: ; preds = %entry + %1 = landingpad { i8*, i32 } + filter [0 x i8*] zeroinitializer + %2 = extractvalue { i8*, i32 } %1, 0 + tail call void @__cxa_call_unexpected(i8* %2) + unreachable + +unreachable: ; preds = %entry + unreachable +; CHECK-LABEL: _Z4funcv +; CHECK-NOT: .debug_frame +; CHECK: .cfi_personality +; CHECK: .cfi_endproc +} + +declare i8* @__cxa_allocate_exception(i64) local_unnamed_addr + +declare void @__cxa_throw(i8*, i8*, i8*) local_unnamed_addr + +declare i32 @__gxx_personality_v0(...) + +declare void @__cxa_call_unexpected(i8*) local_unnamed_addr + + +attributes #0 = { noreturn nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="ppc64le" "target-features"="+altivec,+bpermd,+crypto,+direct-move,+extdiv,+htm,+power8-vector,+vsx,-power9-vector,-qpx" "unsafe-fp-math"="false" "use-soft-float"="false" } + diff --git a/llvm/test/CodeGen/X86/uwtables.ll b/llvm/test/CodeGen/X86/uwtables.ll new file mode 100644 index 0000000..d25492d --- /dev/null +++ b/llvm/test/CodeGen/X86/uwtables.ll @@ -0,0 +1,43 @@ +; RUN: llc -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s + + +@_ZTIi = external constant i8* + +; Function is marked as nounwind but it still throws with __cxa_throw and +; calls __cxa_call_unexpected. +; Need to make sure that we do not only have a debug frame. +; Function Attrs: noreturn nounwind +define void @_Z4funcv() local_unnamed_addr #0 personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) { +entry: + %exception = tail call i8* @__cxa_allocate_exception(i64 4) + %0 = bitcast i8* %exception to i32* + store i32 100, i32* %0, align 16 + invoke void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) + to label %unreachable unwind label %lpad + +lpad: ; preds = %entry + %1 = landingpad { i8*, i32 } + filter [0 x i8*] zeroinitializer + %2 = extractvalue { i8*, i32 } %1, 0 + tail call void @__cxa_call_unexpected(i8* %2) + unreachable + +unreachable: ; preds = %entry + unreachable +; CHECK-LABEL: _Z4funcv +; CHECK-NOT: .debug_frame +; CHECK: .cfi_personality +; CHECK: .cfi_endproc +} + +declare i8* @__cxa_allocate_exception(i64) local_unnamed_addr + +declare void @__cxa_throw(i8*, i8*, i8*) local_unnamed_addr + +declare i32 @__gxx_personality_v0(...) + +declare void @__cxa_call_unexpected(i8*) local_unnamed_addr + + +attributes #0 = { noreturn nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="ppc64le" "target-features"="+altivec,+bpermd,+crypto,+direct-move,+extdiv,+htm,+power8-vector,+vsx,-power9-vector,-qpx" "unsafe-fp-math"="false" "use-soft-float"="false" } + diff --git a/llvm/test/CodeGen/X86/x86-shrink-wrap-unwind.ll b/llvm/test/CodeGen/X86/x86-shrink-wrap-unwind.ll index bac8393..f1f81da 100644 --- a/llvm/test/CodeGen/X86/x86-shrink-wrap-unwind.ll +++ b/llvm/test/CodeGen/X86/x86-shrink-wrap-unwind.ll @@ -237,6 +237,7 @@ attributes #5 = { nounwind readonly ssp uwtable "split-stack" } ; CHECK: push ; ; Jump to throw_exception: +; CHECK-NEXT: .cfi_def_cfa_offset ; CHECK-NEXT: testb $1, %dil ; CHECK-NEXT: jne [[THROW_LABEL:LBB[0-9_]+]] ; Else return exit -- 2.7.4