The following constraints hold for swifterror values:
A swifterror value (either the parameter or the alloca) can only
be loaded and stored from, or used as a swifterror argument.
This patch updates instcombine to not try to convert a bitcast of a
function into a bitcast of a swifterror argument.
Reviewed By: rjmccall
Differential Revision: https://reviews.llvm.org/D90258
if (Call.isInAllocaArgument(i))
return false; // Cannot transform to and from inalloca.
+ if (CallerPAL.hasParamAttribute(i, Attribute::SwiftError))
+ return false;
+
// If the parameter is passed as a byval argument, then we have to have a
// sized type and the sized type has to have the same size as the old type.
if (ParamTy != ActTy && CallerPAL.hasParamAttribute(i, Attribute::ByVal)) {
--- /dev/null
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -instcombine -S %s | FileCheck %s
+
+; The swifterror value can only be loaded, stored or used as swifterror
+; argument. Make sure we do not try to turn the function bitcast into an
+; argument bitcast.
+define swiftcc void @spam(i32** swifterror %arg) {
+; CHECK-LABEL: @spam(
+; CHECK-NEXT: bb:
+; CHECK-NEXT: call swiftcc void bitcast (void (i64**)* @widget to void (i32**)*)(i32** swifterror [[ARG:%.*]])
+; CHECK-NEXT: ret void
+;
+bb:
+ call swiftcc void bitcast (void (i64**)* @widget to void (i32**)*)(i32** swifterror %arg)
+ ret void
+}
+
+declare swiftcc void @widget(i64**)