From ea0eec69f16e0f1b00fec413986e4e44f6f627fa Mon Sep 17 00:00:00 2001 From: Tim Northover Date: Wed, 20 Jan 2021 10:14:03 +0000 Subject: IR+AArch64: add a "swiftasync" argument attribute. This extends any frame record created in the function to include that parameter, passed in X22. The new record looks like [X22, FP, LR] in memory, and FP is stored with 0b0001 in bits 63:60 (CodeGen assumes they are 0b0000 in normal operation). The effect of this is that tools walking the stack should expect to see one of three values there: * 0b0000 => a normal, non-extended record with just [FP, LR] * 0b0001 => the extended record [X22, FP, LR] * 0b1111 => kernel space, and a non-extended record. All other values are currently reserved. If compiling for arm64e this context pointer is address-discriminated with the discriminator 0xc31a and the DB (process-specific) key. There is also an "i8** @llvm.swift.async.context.addr()" intrinsic providing front-ends access to this slot (and forcing its creation initialized to nullptr if necessary). --- llvm/lib/Bitcode/Writer/BitcodeWriter.cpp | 2 ++ 1 file changed, 2 insertions(+) (limited to 'llvm/lib/Bitcode/Writer/BitcodeWriter.cpp') diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp index 50fb3d4..c5ff561 100644 --- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp +++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp @@ -736,6 +736,8 @@ static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind) { return bitc::ATTR_KIND_SWIFT_ERROR; case Attribute::SwiftSelf: return bitc::ATTR_KIND_SWIFT_SELF; + case Attribute::SwiftAsync: + return bitc::ATTR_KIND_SWIFT_ASYNC; case Attribute::UWTable: return bitc::ATTR_KIND_UW_TABLE; case Attribute::VScaleRange: -- cgit v1.1