Add speculatable function attribute

This attribute tells the optimizer that the function may be speculated.

Patch by Tom Stellard

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301680 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 44 insertions, 0 deletions

diff --git a/test/Verifier/speculatable-callsite-invalid.ll b/test/Verifier/speculatable-callsite-invalid.ll
new file mode 100644
index 000000000000..f9a1adfe947d
--- /dev/null
+++ b/test/Verifier/speculatable-callsite-invalid.ll
@@ -0,0 +1,24 @@
+; RUN: not llvm-as %s -o /dev/null 2>&1 | FileCheck %s
+
+; Make sure that speculatable is not allowed on a call site if the
+; declaration is not also speculatable.
+
+declare i32 @not_speculatable()
+
+; CHECK: speculatable attribute may not apply to call sites
+; CHECK-NEXT: %ret = call i32 @not_speculatable() #0
+define i32 @call_not_speculatable() {
+  %ret = call i32 @not_speculatable() #0
+  ret i32 %ret
+}
+
+@gv = internal unnamed_addr constant i32 0
+
+; CHECK: speculatable attribute may not apply to call sites
+; CHECK-NEXT: %ret = call float bitcast (i32* @gv to float ()*)() #0
+define float @call_bitcast_speculatable() {
+  %ret = call float bitcast (i32* @gv to float()*)() #0
+  ret float %ret
+}
+
+attributes #0 = { speculatable }
diff --git a/test/Verifier/speculatable-callsite.ll b/test/Verifier/speculatable-callsite.ll
new file mode 100644
index 000000000000..fafed831cf96
--- /dev/null
+++ b/test/Verifier/speculatable-callsite.ll
@@ -0,0 +1,20 @@
+; RUN: llvm-as %s -o /dev/null
+
+; Make sure speculatable is accepted on a call site if the declaration
+; is also speculatable.
+
+declare i32 @speculatable() #0
+
+; Make sure this the attribute is accepted on the call site if the
+; declaration matches.
+define i32 @call_speculatable() {
+  %ret = call i32 @speculatable() #0
+  ret i32 %ret
+}
+
+define float @call_bitcast_speculatable() {
+  %ret = call float bitcast (i32()* @speculatable to float()*)() #0
+  ret float %ret
+}
+
+attributes #0 = { speculatable }