From c4df1d182c13c0665868e39aa7ee1e967368db40 Mon Sep 17 00:00:00 2001 From: Heejin Ahn Date: Wed, 22 Aug 2018 00:20:02 +0000 Subject: [PATCH] [WebAssembly] Change comments on SP writing back (NFC) Summary: We now write back not to memory but to __stack_pointer global. Reviewers: dschuff Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits Differential Revision: https://reviews.llvm.org/D51074 llvm-svn: 340372 --- llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp | 5 +++-- llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h | 3 ++- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp index 9e33ed7..8b156ec 100644 --- a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp +++ b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp @@ -99,8 +99,9 @@ bool WebAssemblyFrameLowering::needsSP(const MachineFunction &MF, } /// Returns true if the local user-space stack pointer needs to be written back -/// to memory by this function (this is not meaningful if needsSP is false). If -/// false, the stack red zone can be used and only a local SP is needed. +/// to __stack_pointer global by this function (this is not meaningful if +/// needsSP is false). If false, the stack red zone can be used and only a local +/// SP is needed. bool WebAssemblyFrameLowering::needsSPWriteback( const MachineFunction &MF, const MachineFrameInfo &MFI) const { assert(needsSP(MF, MFI)); diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h index e888aaf..5e744ad 100644 --- a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h +++ b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h @@ -24,7 +24,8 @@ class MachineFrameInfo; class WebAssemblyFrameLowering final : public TargetFrameLowering { public: /// Size of the red zone for the user stack (leaf functions can use this much - /// space below the stack pointer without writing it back to memory). + /// space below the stack pointer without writing it back to __stack_pointer + /// global). // TODO: (ABI) Revisit and decide how large it should be. static const size_t RedZoneSize = 128; -- 2.7.4