Initial commit of llgo.

llvm-svn: 222857

1 files changed, 72 insertions, 0 deletions

diff --git a/llgo/irgen/errors.go b/llgo/irgen/errors.go
new file mode 100644
index 00000000000..73f498ebdd0
--- /dev/null
+++ b/llgo/irgen/errors.go
@@ -0,0 +1,72 @@
+//===- errors.go - IR generation for run-time panics ----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements IR generation for triggering run-time panics.
+//
+//===----------------------------------------------------------------------===//
+
+package irgen
+
+import (
+	"llvm.org/llvm/bindings/go/llvm"
+)
+
+const (
+	// From go-runtime-error.c
+	gccgoRuntimeErrorSLICE_INDEX_OUT_OF_BOUNDS  = 0
+	gccgoRuntimeErrorARRAY_INDEX_OUT_OF_BOUNDS  = 1
+	gccgoRuntimeErrorSTRING_INDEX_OUT_OF_BOUNDS = 2
+	gccgoRuntimeErrorSLICE_SLICE_OUT_OF_BOUNDS  = 3
+	gccgoRuntimeErrorARRAY_SLICE_OUT_OF_BOUNDS  = 4
+	gccgoRuntimeErrorSTRING_SLICE_OUT_OF_BOUNDS = 5
+	gccgoRuntimeErrorNIL_DEREFERENCE            = 6
+	gccgoRuntimeErrorMAKE_SLICE_OUT_OF_BOUNDS   = 7
+	gccgoRuntimeErrorMAKE_MAP_OUT_OF_BOUNDS     = 8
+	gccgoRuntimeErrorMAKE_CHAN_OUT_OF_BOUNDS    = 9
+	gccgoRuntimeErrorDIVISION_BY_ZERO           = 10
+	gccgoRuntimeErrorCount                      = 11
+)
+
+func (fr *frame) setBranchWeightMetadata(br llvm.Value, trueweight, falseweight uint64) {
+	mdprof := llvm.MDKindID("prof")
+
+	mdnode := llvm.MDNode([]llvm.Value{
+		llvm.MDString("branch_weights"),
+		llvm.ConstInt(llvm.Int32Type(), trueweight, false),
+		llvm.ConstInt(llvm.Int32Type(), falseweight, false),
+	})
+
+	br.SetMetadata(mdprof, mdnode)
+}
+
+func (fr *frame) condBrRuntimeError(cond llvm.Value, errcode uint64) {
+	if cond.IsNull() {
+		return
+	}
+
+	errorbb := fr.runtimeErrorBlocks[errcode]
+	newbb := errorbb.C == nil
+	if newbb {
+		errorbb = llvm.AddBasicBlock(fr.function, "")
+		fr.runtimeErrorBlocks[errcode] = errorbb
+	}
+
+	contbb := llvm.AddBasicBlock(fr.function, "")
+
+	br := fr.builder.CreateCondBr(cond, errorbb, contbb)
+	fr.setBranchWeightMetadata(br, 1, 1000)
+
+	if newbb {
+		fr.builder.SetInsertPointAtEnd(errorbb)
+		fr.runtime.runtimeError.call(fr, llvm.ConstInt(llvm.Int32Type(), errcode, false))
+		fr.builder.CreateUnreachable()
+	}
+
+	fr.builder.SetInsertPointAtEnd(contbb)
+}