Merge pull request #303 from maleadt/tb/poison

Add support for poison values.

Author: maleadt

src/core/value.jl

@@ -40,7 +40,7 @@ end
 
 ## general APIs
 
-export llvmtype, llvmeltype, name, name!, replace_uses!, isconstant, isundef, context
+export llvmtype, llvmeltype, name, name!, replace_uses!, isconstant, isundef, ispoison, context
 
 llvmtype(val::Value) = LLVMType(API.LLVMTypeOf(val))
 llvmeltype(val::Value) = eltype(llvmtype(val))
@@ -59,6 +59,8 @@ isconstant(val::Value) = convert(Core.Bool, API.LLVMIsConstant(val))
 
 isundef(val::Value) = convert(Core.Bool, API.LLVMIsUndef(val))
 
+ispoison(val::Value) = convert(Core.Bool, API.LLVMIsPoison(val))
+
 context(val::Value) = Context(API.LLVMGetValueContext(val))
 
 

src/core/value/constant.jl

@@ -20,7 +20,7 @@ abstract type Instruction <: User end
 
 ## data
 
-export ConstantData, PointerNull, UndefValue, ConstantInt, ConstantFP
+export ConstantData, PointerNull, UndefValue, PoisonValue, ConstantInt, ConstantFP
 
 abstract type ConstantData <: Constant end
 
@@ -40,6 +40,14 @@ register(UndefValue, API.LLVMUndefValueValueKind)
 
 UndefValue(typ::LLVMType) = UndefValue(API.LLVMGetUndef(typ))
 
+@static if version() >= v"12"
+@checked struct PoisonValue <: ConstantData # XXX: actually <: UndefValue
+    ref::API.LLVMValueRef
+end
+register(PoisonValue, API.LLVMPoisonValueValueKind)
+
+PoisonValue(typ::LLVMType) = PoisonValue(API.LLVMGetPoison(typ))
+end
 
 @checked struct ConstantInt <: ConstantData
     ref::API.LLVMValueRef

test/core.jl

@@ -322,6 +322,13 @@ Context() do ctx
         @test val isa LLVM.Constant
     end
 
+    if LLVM.version() >= v"12"
+        let val = PoisonValue(typ)
+            @test ispoison(val)
+            @test val isa LLVM.Constant
+        end
+    end
+
     end
 end