[Statepoints] Support for "patchable" statepoints.

Summary:
This change adds two new parameters to the statepoint intrinsic, `i64 id`
and `i32 num_patch_bytes`.  `id` gets propagated to the ID field
in the generated StackMap section.  If the `num_patch_bytes` is
non-zero then the statepoint is lowered to `num_patch_bytes` bytes of
nops instead of a call (the spill and reload code remains unchanged).
A non-zero `num_patch_bytes` is useful in situations where a language
runtime requires complete control over how a call is lowered.

This change brings statepoints one step closer to patchpoints.  With
some additional work (that is not part of this patch) it should be
possible to get rid of `TargetOpcode::STATEPOINT` altogether.

PlaceSafepoints generates `statepoint` wrappers with `id` set to
`0xABCDEF00` (the old default value for the ID reported in the stackmap)
and `num_patch_bytes` set to `0`.  This can be made more sophisticated
later.

Reviewers: reames, pgavlin, swaroop.sridhar, AndyAyers

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9546

llvm-svn: 237214
diff --git a/llvm/test/Verifier/invalid-patchable-statepoint.ll b/llvm/test/Verifier/invalid-patchable-statepoint.ll
new file mode 100644
index 0000000..4783fa5
--- /dev/null
+++ b/llvm/test/Verifier/invalid-patchable-statepoint.ll
@@ -0,0 +1,14 @@
+; RUN: not opt -verify 2>&1 < %s | FileCheck %s
+
+; CHECK: gc.statepoint must have null as call target if number of patchable bytes is non zero
+
+define i1 @invalid_patchable_statepoint() gc "statepoint-example" {
+entry:
+  %safepoint_token = tail call i32 (i64, i32, i1 ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_i1f(i64 0, i32 3, i1 ()* @func, i32 0, i32 0, i32 0, i32 0)
+  %call1 = call i1 @llvm.experimental.gc.result.i1(i32 %safepoint_token)
+  ret i1 %call1
+}
+
+declare i32 @llvm.experimental.gc.statepoint.p0f_i1f(i64, i32, i1 ()*, i32, i32, ...)
+declare i1 @llvm.experimental.gc.result.i1(i32)
+declare i1 @func()
diff --git a/llvm/test/Verifier/invalid-statepoint.ll b/llvm/test/Verifier/invalid-statepoint.ll
index d3a5bb8..6c3525a 100644
--- a/llvm/test/Verifier/invalid-statepoint.ll
+++ b/llvm/test/Verifier/invalid-statepoint.ll
@@ -5,16 +5,16 @@
 declare zeroext i1 @return0i1()
 
 ; Function Attrs: nounwind
-declare i32 @llvm.experimental.gc.statepoint.p0f0i1f(i1 ()*, i32, i32, ...) #0
+declare i32 @llvm.experimental.gc.statepoint.p0f0i1f(i64, i32, i1 ()*, i32, i32, ...) #0
 
 ; Function Attrs: nounwind
 declare i32 addrspace(1)* @llvm.experimental.gc.relocate.p1i32(i32, i32, i32) #0
 
 define i32 addrspace(1)* @0(i32 addrspace(1)* %dparam) {
   %a00 = load i32, i32 addrspace(1)* %dparam
-  %to0 = call i32 (i1 ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f0i1f(i1 ()* @return0i1, i32 9, i32 0, i2 0, i32 addrspace(1)* %dparam)
-  %relocate = call i32 addrspace(1)* @llvm.experimental.gc.relocate.p1i32(i32 %to0, i32 0, i32 4)
+  %to0 = call i32 (i64, i32, i1 ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f0i1f(i64 0, i32 0, i1 ()* @return0i1, i32 9, i32 0, i2 0, i32 addrspace(1)* %dparam)
+  %relocate = call i32 addrspace(1)* @llvm.experimental.gc.relocate.p1i32(i32 %to0, i32 2, i32 6)
   ret i32 addrspace(1)* %relocate
 }
 
-attributes #0 = { nounwind }
+attributes #0 = { nounwind }
\ No newline at end of file
diff --git a/llvm/test/Verifier/invalid-statepoint2.ll b/llvm/test/Verifier/invalid-statepoint2.ll
index 0d5c2c9..c8b453c 100644
--- a/llvm/test/Verifier/invalid-statepoint2.ll
+++ b/llvm/test/Verifier/invalid-statepoint2.ll
@@ -5,15 +5,14 @@
 declare void @use(...)
 declare i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32, i32, i32)
 declare i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32, i32, i32)
-declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()*, i32, i32, ...)
+declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(i64, i32, void ()*, i32, i32, ...)
 declare i32 @"personality_function"()
 
 ;; Basic usage
 define i64 addrspace(1)* @test1(i8 addrspace(1)* %arg, i32 %val) gc "statepoint-example" {
 entry:
   %cast = bitcast i8 addrspace(1)* %arg to i64 addrspace(1)*
-  %safepoint_token = call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* undef, i32 0, i32 0, i32 0, i32 %val, i32 0, i32 0, i32 0, i32 10, i32 0, i8 addrspace(1)* %arg, i64 addrspace(1)* %cast, i8 addrspace(1)* %arg, i8 addrspace(1)* %arg)
-  %reloc = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 10, i32 11)
+  %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* undef, i32 0, i32 0, i32 0, i32 %val, i32 0, i32 0, i32 0, i32 10, i32 0, i8 addrspace(1)* %arg, i64 addrspace(1)* %cast, i8 addrspace(1)* %arg, i8 addrspace(1)* %arg)
+  %reloc = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 12, i32 13)
   ret i64 addrspace(1)* %reloc
 }
-
diff --git a/llvm/test/Verifier/statepoint.ll b/llvm/test/Verifier/statepoint.ll
index 7c1cb3e..05a3edd 100644
--- a/llvm/test/Verifier/statepoint.ll
+++ b/llvm/test/Verifier/statepoint.ll
@@ -3,18 +3,18 @@
 declare void @use(...)
 declare i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32, i32, i32)
 declare i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32, i32, i32)
-declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()*, i32, i32, ...)
+declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(i64, i32, void ()*, i32, i32, ...)
 declare i32 @"personality_function"()
 
 ;; Basic usage
 define i64 addrspace(1)* @test1(i8 addrspace(1)* %arg) gc "statepoint-example" {
 entry:
   %cast = bitcast i8 addrspace(1)* %arg to i64 addrspace(1)*
-  %safepoint_token = call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* undef, i32 0, i32 0, i32 0, i32 5, i32 0, i32 0, i32 0, i32 10, i32 0, i8 addrspace(1)* %arg, i64 addrspace(1)* %cast, i8 addrspace(1)* %arg, i8 addrspace(1)* %arg)
-  %reloc = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 10, i32 11)
+  %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* undef, i32 0, i32 0, i32 0, i32 5, i32 0, i32 0, i32 0, i32 10, i32 0, i8 addrspace(1)* %arg, i64 addrspace(1)* %cast, i8 addrspace(1)* %arg, i8 addrspace(1)* %arg)
+  %reloc = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 12, i32 13)
   ;; It is perfectly legal to relocate the same value multiple times...
-  %reloc2 = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 10, i32 11)
-  %reloc3 = call i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %safepoint_token, i32 11, i32 10)
+  %reloc2 = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 12, i32 13)
+  %reloc3 = call i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %safepoint_token, i32 13, i32 12)
   ret i64 addrspace(1)* %reloc
 ; CHECK-LABEL: test1
 ; CHECK: statepoint
@@ -39,8 +39,8 @@
   ret void
 
 equal:
-  %safepoint_token = call i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* undef, i32 0, i32 0, i32 0, i32 5, i32 0, i32 0, i32 0, i32 10, i32 0, i8 addrspace(1)* %arg, i64 addrspace(1)* %cast, i8 addrspace(1)* %arg, i8 addrspace(1)* %arg)
-  %reloc = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 10, i32 11)
+  %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* undef, i32 0, i32 0, i32 0, i32 5, i32 0, i32 0, i32 0, i32 10, i32 0, i8 addrspace(1)* %arg, i64 addrspace(1)* %cast, i8 addrspace(1)* %arg, i8 addrspace(1)* %arg)
+  %reloc = call i64 addrspace(1)* @llvm.experimental.gc.relocate.p1i64(i32 %safepoint_token, i32 12, i32 13)
   call void undef(i64 addrspace(1)* %reloc)
   ret void
 ; CHECK-LABEL: test2
@@ -57,7 +57,7 @@
 entry:
   ; CHECK-LABEL: entry
   ; CHECK: statepoint
-  %0 = invoke i32 (void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(void ()* undef, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0, i8 addrspace(1)* %obj, i8 addrspace(1)* %obj1)
+  %0 = invoke i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* undef, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0, i8 addrspace(1)* %obj, i8 addrspace(1)* %obj1)
           to label %normal_dest unwind label %exceptional_return
 
 normal_dest:
@@ -65,8 +65,8 @@
   ; CHECK: gc.relocate
   ; CHECK: gc.relocate
   ; CHECK: ret
-  %obj.relocated = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %0, i32 10, i32 10)
-  %obj1.relocated = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %0, i32 10, i32 10)
+  %obj.relocated = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %0, i32 12, i32 12)
+  %obj1.relocated = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %0, i32 12, i32 12)
   ret i8 addrspace(1)* %obj.relocated
 
 exceptional_return:
@@ -76,8 +76,7 @@
   %landing_pad = landingpad { i8*, i32 } personality i32 ()* @"personality_function"
           cleanup
   %relocate_token = extractvalue { i8*, i32 } %landing_pad, 1
-  %obj.relocated1 = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %relocate_token, i32 10, i32 10)
-  %obj1.relocated1 = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %relocate_token, i32 10, i32 10)
+  %obj.relocated1 = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %relocate_token, i32 12, i32 12)
+  %obj1.relocated1 = call coldcc i8 addrspace(1)* @llvm.experimental.gc.relocate.p1i8(i32 %relocate_token, i32 12, i32 12)
   ret i8 addrspace(1)* %obj1.relocated1
 }
-