ci: add support for LLVM 15

This commit switches to LLVM 15 everywhere by default, while still
keeping LLVM 14 support.

transform/interface-lowering.go

@@ -305,7 +305,9 @@ func (p *lowerInterfacesPass) addTypeMethods(t *typeInfo, methodSet llvm.Value)
 		// no methods or methods already read
 		return
 	}
-	methodSet = methodSet.Operand(0) // get global from GEP
+	if !methodSet.IsAConstantExpr().IsNil() && methodSet.Opcode() == llvm.GetElementPtr {
+		methodSet = methodSet.Operand(0) // get global from GEP, for LLVM 14 (non-opaque pointers)
+	}
 
 	// This type has methods, collect all methods of this type.
 	t.methodSet = methodSet

transform/interrupt.go

@@ -36,9 +36,8 @@ func LowerInterrupts(mod llvm.Module) []error {
 	handleMap := map[int64][]llvm.Value{}
 	handleType := mod.GetTypeByName("runtime/interrupt.handle")
 	if !handleType.IsNil() {
-		handlePtrType := llvm.PointerType(handleType, 0)
 		for global := mod.FirstGlobal(); !global.IsNil(); global = llvm.NextGlobal(global) {
-			if global.Type() != handlePtrType {
+			if global.GlobalValueType() != handleType {
 				continue
 			}
 

transform/llvm.go

@@ -80,6 +80,12 @@ func replaceGlobalIntWithArray(mod llvm.Module, name string, buf interface{}) ll
 // stripPointerCasts strips instruction pointer casts (getelementptr and
 // bitcast) and returns the original value without the casts.
 func stripPointerCasts(value llvm.Value) llvm.Value {
+	if !value.IsAConstantExpr().IsNil() {
+		switch value.Opcode() {
+		case llvm.GetElementPtr, llvm.BitCast:
+			return stripPointerCasts(value.Operand(0))
+		}
+	}
 	if !value.IsAInstruction().IsNil() {
 		switch value.InstructionOpcode() {
 		case llvm.GetElementPtr, llvm.BitCast:

transform/reflect.go

@@ -251,7 +251,10 @@ func LowerReflect(mod llvm.Module) {
 			// a pointer to a runtime.structField array and therefore a
 			// bitcast. This global should be erased separately, otherwise
 			// typecode objects cannot be erased.
-			structFields := references.Operand(0)
+			structFields := references
+			if !structFields.IsAConstantExpr().IsNil() && structFields.Opcode() == llvm.BitCast {
+				structFields = structFields.Operand(0) // get global from bitcast, for LLVM 14 compatibility (non-opaque pointers)
+			}
 			structFields.EraseFromParentAsGlobal()
 		}
 	}
@@ -460,7 +463,7 @@ func (state *typeCodeAssignmentState) getStructTypeNum(typecode llvm.Value) int
 
 	// Get the fields this struct type contains.
 	// The struct number will be the start index of
-	structTypeGlobal := state.builder.CreateExtractValue(typecode.Initializer(), 0, "").Operand(0).Initializer()
+	structTypeGlobal := stripPointerCasts(state.builder.CreateExtractValue(typecode.Initializer(), 0, "")).Initializer()
 	numFields := structTypeGlobal.Type().ArrayLength()
 
 	// The first data that is stored in the struct sidetable is the number of
@@ -483,7 +486,7 @@ func (state *typeCodeAssignmentState) getStructTypeNum(typecode llvm.Value) int
 		if nameGlobal == llvm.ConstPointerNull(nameGlobal.Type()) {
 			panic("compiler: no name for this struct field")
 		}
-		fieldNameBytes := getGlobalBytes(nameGlobal.Operand(0), state.builder)
+		fieldNameBytes := getGlobalBytes(stripPointerCasts(nameGlobal), state.builder)
 		fieldNameNumber := state.getStructNameNumber(fieldNameBytes)
 
 		// See whether this struct field has an associated tag, and if so,
@@ -493,7 +496,7 @@ func (state *typeCodeAssignmentState) getStructTypeNum(typecode llvm.Value) int
 		tagNumber := 0
 		if tagGlobal != llvm.ConstPointerNull(tagGlobal.Type()) {
 			hasTag = true
-			tagBytes := getGlobalBytes(tagGlobal.Operand(0), state.builder)
+			tagBytes := getGlobalBytes(stripPointerCasts(tagGlobal), state.builder)
 			tagNumber = state.getStructNameNumber(tagBytes)
 		}
 

transform/rtcalls.go

@@ -139,14 +139,13 @@ func OptimizeReflectImplements(mod llvm.Module) {
 		if call.IsACallInst().IsNil() {
 			continue
 		}
-		interfaceTypeBitCast := call.Operand(2)
-		if interfaceTypeBitCast.IsAConstantExpr().IsNil() || interfaceTypeBitCast.Opcode() != llvm.BitCast {
+		interfaceType := stripPointerCasts(call.Operand(2))
+		if interfaceType.IsAGlobalVariable().IsNil() {
 			// The asserted interface is not constant, so can't optimize this
 			// code.
 			continue
 		}
 
-		interfaceType := interfaceTypeBitCast.Operand(0)
 		if strings.HasPrefix(interfaceType.Name(), "reflect/types.type:named:") {
 			// Get the underlying type.
 			interfaceType = builder.CreateExtractValue(interfaceType.Initializer(), 0, "")