WholeProgramDevirt: Change internal vcall data structures to match summary.

Group calls into constant and non-constant arguments up front, and use uint64_t
instead of ConstantInt to represent constant arguments. The goal is to allow
the information from the summary to fit naturally into this data structure in
a future change (specifically, it will be added to CallSiteInfo).

This has two side effects:
- We disallow VCP for constant integer arguments of width >64 bits.
- We remove the restriction that the bitwidth of a vcall's argument and return
  types must match those of the vfunc definitions.
I don't expect either of these to matter in practice. The first case is
uncommon, and the second one will lead to UB (so we can do anything we like).

Differential Revision: https://reviews.llvm.org/D29744

llvm-svn: 295110

1 files changed, 42 insertions, 12 deletions

diff --git a/llvm/test/Transforms/WholeProgramDevirt/vcp-too-wide-ints.ll b/llvm/test/Transforms/WholeProgramDevirt/vcp-too-wide-ints.ll
index 7ac24777cf2..c24c3b4be68 100644
--- a/llvm/test/Transforms/WholeProgramDevirt/vcp-too-wide-ints.ll
+++ b/llvm/test/Transforms/WholeProgramDevirt/vcp-too-wide-ints.ll
@@ -3,33 +3,63 @@
 target datalayout = "e-p:64:64"
 target triple = "x86_64-unknown-linux-gnu"
 
-@vt1 = constant [1 x i8*] [i8* bitcast (i128 (i8*, i128)* @vf1 to i8*)], !type !0
-@vt2 = constant [1 x i8*] [i8* bitcast (i128 (i8*, i128)* @vf2 to i8*)], !type !0
+@vt1 = constant [1 x i8*] [i8* bitcast (i64 (i8*, i128)* @vf1 to i8*)], !type !0
+@vt2 = constant [1 x i8*] [i8* bitcast (i64 (i8*, i128)* @vf2 to i8*)], !type !0
+@vt3 = constant [1 x i8*] [i8* bitcast (i128 (i8*, i64)* @vf3 to i8*)], !type !1
+@vt4 = constant [1 x i8*] [i8* bitcast (i128 (i8*, i64)* @vf4 to i8*)], !type !1
 
-define i128 @vf1(i8* %this, i128 %arg) readnone {
-  ret i128 %arg
+define i64 @vf1(i8* %this, i128 %arg) readnone {
+  %argtrunc = trunc i128 %arg to i64
+  ret i64 %argtrunc
 }
 
-define i128 @vf2(i8* %this, i128 %arg) readnone {
-  ret i128 %arg
+define i64 @vf2(i8* %this, i128 %arg) readnone {
+  %argtrunc = trunc i128 %arg to i64
+  ret i64 %argtrunc
 }
 
-; CHECK: define i128 @call
-define i128 @call(i8* %obj) {
+define i128 @vf3(i8* %this, i64 %arg) readnone {
+  %argzext = zext i64 %arg to i128
+  ret i128 %argzext
+}
+
+define i128 @vf4(i8* %this, i64 %arg) readnone {
+  %argzext = zext i64 %arg to i128
+  ret i128 %argzext
+}
+
+; CHECK: define i64 @call1
+define i64 @call1(i8* %obj) {
+  %vtableptr = bitcast i8* %obj to [1 x i8*]**
+  %vtable = load [1 x i8*]*, [1 x i8*]** %vtableptr
+  %vtablei8 = bitcast [1 x i8*]* %vtable to i8*
+  %p = call i1 @llvm.type.test(i8* %vtablei8, metadata !"typeid1")
+  call void @llvm.assume(i1 %p)
+  %fptrptr = getelementptr [1 x i8*], [1 x i8*]* %vtable, i32 0, i32 0
+  %fptr = load i8*, i8** %fptrptr
+  %fptr_casted = bitcast i8* %fptr to i64 (i8*, i128)*
+  ; CHECK: call i64 %
+  %result = call i64 %fptr_casted(i8* %obj, i128 1)
+  ret i64 %result
+}
+
+; CHECK: define i128 @call2
+define i128 @call2(i8* %obj) {
   %vtableptr = bitcast i8* %obj to [1 x i8*]**
   %vtable = load [1 x i8*]*, [1 x i8*]** %vtableptr
   %vtablei8 = bitcast [1 x i8*]* %vtable to i8*
-  %p = call i1 @llvm.type.test(i8* %vtablei8, metadata !"typeid")
+  %p = call i1 @llvm.type.test(i8* %vtablei8, metadata !"typeid2")
   call void @llvm.assume(i1 %p)
   %fptrptr = getelementptr [1 x i8*], [1 x i8*]* %vtable, i32 0, i32 0
   %fptr = load i8*, i8** %fptrptr
-  %fptr_casted = bitcast i8* %fptr to i128 (i8*, i128)*
+  %fptr_casted = bitcast i8* %fptr to i128 (i8*, i64)*
   ; CHECK: call i128 %
-  %result = call i128 %fptr_casted(i8* %obj, i128 1)
+  %result = call i128 %fptr_casted(i8* %obj, i64 1)
   ret i128 %result
 }
 
 declare i1 @llvm.type.test(i8*, metadata)
 declare void @llvm.assume(i1)
 
-!0 = !{i32 0, !"typeid"}
+!0 = !{i32 0, !"typeid1"}
+!1 = !{i32 0, !"typeid2"}