Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html
This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.
This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.
There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.
Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii
Differential Revision: https://reviews.llvm.org/D53765
llvm-svn: 353563
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index f4a539e..a15ad55 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -2777,6 +2777,41 @@
Vals.push_back(VE.getValueID(CatchSwitch.getUnwindDest()));
break;
}
+ case Instruction::CallBr: {
+ const CallBrInst *CBI = cast<CallBrInst>(&I);
+ const Value *Callee = CBI->getCalledValue();
+ FunctionType *FTy = CBI->getFunctionType();
+
+ if (CBI->hasOperandBundles())
+ writeOperandBundles(CBI, InstID);
+
+ Code = bitc::FUNC_CODE_INST_CALLBR;
+
+ Vals.push_back(VE.getAttributeListID(CBI->getAttributes()));
+
+ Vals.push_back(CBI->getCallingConv() << bitc::CALL_CCONV |
+ 1 << bitc::CALL_EXPLICIT_TYPE);
+
+ Vals.push_back(VE.getValueID(CBI->getDefaultDest()));
+ Vals.push_back(CBI->getNumIndirectDests());
+ for (unsigned i = 0, e = CBI->getNumIndirectDests(); i != e; ++i)
+ Vals.push_back(VE.getValueID(CBI->getIndirectDest(i)));
+
+ Vals.push_back(VE.getTypeID(FTy));
+ pushValueAndType(Callee, InstID, Vals);
+
+ // Emit value #'s for the fixed parameters.
+ for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
+ pushValue(I.getOperand(i), InstID, Vals); // fixed param.
+
+ // Emit type/value pairs for varargs params.
+ if (FTy->isVarArg()) {
+ for (unsigned i = FTy->getNumParams(), e = CBI->getNumArgOperands();
+ i != e; ++i)
+ pushValueAndType(I.getOperand(i), InstID, Vals); // vararg
+ }
+ break;
+ }
case Instruction::Unreachable:
Code = bitc::FUNC_CODE_INST_UNREACHABLE;
AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
diff --git a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
index f2f11c1..c735efa 100644
--- a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -414,10 +414,8 @@
EnumerateMetadata(&F, MD->getMetadata());
}
EnumerateType(I.getType());
- if (const CallInst *CI = dyn_cast<CallInst>(&I))
- EnumerateAttributes(CI->getAttributes());
- else if (const InvokeInst *II = dyn_cast<InvokeInst>(&I))
- EnumerateAttributes(II->getAttributes());
+ if (const auto *Call = dyn_cast<CallBase>(&I))
+ EnumerateAttributes(Call->getAttributes());
// Enumerate metadata attached with this instruction.
MDs.clear();