r261557 - [WebAssembly] Lower va_arg in clang.

[Dan Gohman via cfe-commits]

Author: djg
Date: Mon Feb 22 13:17:40 2016
New Revision: 261557

URL: http://llvm.org/viewvc/llvm-project?rev=261557&view=rev
Log:
[WebAssembly] Lower va_arg in clang.

This uses the general emitVoidPtrVAArg lowering logic for everything, since
this supports all types, and we don't have any special requirements.

Added:
    cfe/trunk/test/CodeGen/wasm-varargs.c
Modified:
    cfe/trunk/lib/CodeGen/TargetInfo.cpp

Modified: cfe/trunk/lib/CodeGen/TargetInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/TargetInfo.cpp?rev=261557&r1=261556&r2=261557&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/TargetInfo.cpp (original)
+++ cfe/trunk/lib/CodeGen/TargetInfo.cpp Mon Feb 22 13:17:40 2016
@@ -616,6 +616,9 @@ private:
     for (auto &Arg : FI.arguments())
       Arg.info = classifyArgumentType(Arg.type);
   }
+
+  Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
+                    QualType Ty) const override;
 };
 
 class WebAssemblyTargetCodeGenInfo final : public TargetCodeGenInfo {
@@ -667,6 +670,14 @@ ABIArgInfo WebAssemblyABIInfo::classifyR
   return DefaultABIInfo::classifyReturnType(RetTy);
 }
 
+Address WebAssemblyABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
+                                      QualType Ty) const {
+  return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect=*/ false,
+                          getContext().getTypeInfoInChars(Ty),
+                          CharUnits::fromQuantity(4),
+                          /*AllowHigherAlign=*/ true);
+}
+
 //===----------------------------------------------------------------------===//
 // le32/PNaCl bitcode ABI Implementation
 //

Added: cfe/trunk/test/CodeGen/wasm-varargs.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/wasm-varargs.c?rev=261557&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/wasm-varargs.c (added)
+++ cfe/trunk/test/CodeGen/wasm-varargs.c Mon Feb 22 13:17:40 2016
@@ -0,0 +1,103 @@
+// RUN: %clang_cc1 -triple wasm32-unknown-unknown -o - -emit-llvm %s | FileCheck %s
+
+#include <stdarg.h>
+
+int test_i32(char *fmt, ...) {
+  va_list va;
+
+  va_start(va, fmt);
+  int v = va_arg(va, int);
+  va_end(va);
+
+  return v;
+}
+
+// CHECK-LABEL: define i32 @test_i32(i8*{{.*}} %fmt, ...) {{.*}} {
+// CHECK:   [[FMT_ADDR:%[^,=]+]] = alloca i8*, align 4
+// CHECK:   [[VA:%[^,=]+]] = alloca i8*, align 4
+// CHECK:   [[V:%[^,=]+]] = alloca i32, align 4
+// CHECK:   store i8* %fmt, i8** [[FMT_ADDR]], align 4
+// CHECK:   [[VA1:%[^,=]+]] = bitcast i8** [[VA]] to i8*
+// CHECK:   call void @llvm.va_start(i8* [[VA1]])
+// CHECK:   [[ARGP_CUR:%[^,=]+]] = load i8*, i8** [[VA]], align 4
+// CHECK:   [[ARGP_NEXT:%[^,=]+]] = getelementptr inbounds i8, i8* [[ARGP_CUR]], i32 4
+// CHECK:   store i8* [[ARGP_NEXT]], i8** [[VA]], align 4
+// CHECK:   [[R3:%[^,=]+]] = bitcast i8* [[ARGP_CUR]] to i32*
+// CHECK:   [[R4:%[^,=]+]] = load i32, i32* [[R3]], align 4
+// CHECK:   store i32 [[R4]], i32* [[V]], align 4
+// CHECK:   [[VA2:%[^,=]+]] = bitcast i8** [[VA]] to i8*
+// CHECK:   call void @llvm.va_end(i8* [[VA2]])
+// CHECK:   [[R5:%[^,=]+]] = load i32, i32* [[V]], align 4
+// CHECK:   ret i32 [[R5]]
+// CHECK: }
+
+long long test_i64(char *fmt, ...) {
+  va_list va;
+
+  va_start(va, fmt);
+  long long v = va_arg(va, long long);
+  va_end(va);
+
+  return v;
+}
+
+// CHECK-LABEL: define i64 @test_i64(i8*{{.*}} %fmt, ...) {{.*}} {
+// CHECK:   [[FMT_ADDR:%[^,=]+]] = alloca i8*, align 4
+// CHECK:   [[VA:%[^,=]+]] = alloca i8*, align 4
+// CHECK:   [[V:%[^,=]+]] = alloca i64, align 8
+// CHECK:   store i8* %fmt, i8** [[FMT_ADDR]], align 4
+// CHECK:   [[VA1:%[^,=]+]] = bitcast i8** [[VA]] to i8*
+// CHECK:   call void @llvm.va_start(i8* [[VA1]])
+// CHECK:   [[ARGP_CUR:%[^,=]+]] = load i8*, i8** [[VA]], align 4
+// CHECK:   [[R0:%[^,=]+]] = ptrtoint i8* [[ARGP_CUR]] to i32
+// CHECK:   [[R1:%[^,=]+]] = add i32 [[R0]], 7
+// CHECK:   [[R2:%[^,=]+]] = and i32 [[R1]], -8
+// CHECK:   [[ARGP_CUR_ALIGNED:%[^,=]+]] = inttoptr i32 [[R2]] to i8*
+// CHECK:   [[ARGP_NEXT:%[^,=]+]] = getelementptr inbounds i8, i8* [[ARGP_CUR_ALIGNED]], i32 8
+// CHECK:   store i8* [[ARGP_NEXT]], i8** [[VA]], align 4
+// CHECK:   [[R3:%[^,=]+]] = bitcast i8* [[ARGP_CUR_ALIGNED]] to i64*
+// CHECK:   [[R4:%[^,=]+]] = load i64, i64* [[R3]], align 8
+// CHECK:   store i64 [[R4]], i64* [[V]], align 8
+// CHECK:   [[VA2:%[^,=]+]] = bitcast i8** [[VA]] to i8*
+// CHECK:   call void @llvm.va_end(i8* [[VA2]])
+// CHECK:   [[R5:%[^,=]+]] = load i64, i64* [[V]], align 8
+// CHECK:   ret i64 [[R5]]
+// CHECK: }
+
+struct S {
+    int x;
+    int y;
+    int z;
+};
+
+struct S test_struct(char *fmt, ...) {
+  va_list va;
+
+  va_start(va, fmt);
+  struct S v = va_arg(va, struct S);
+  va_end(va);
+
+  return v;
+}
+
+// CHECK: define void @test_struct([[STRUCT_S:%[^,=]+]]*{{.*}} noalias sret %agg.result, i8*{{.*}} %fmt, ...) {{.*}} {
+// CHECK:   [[FMT_ADDR:%[^,=]+]] = alloca i8*, align 4
+// CHECK:   [[VA:%[^,=]+]] = alloca i8*, align 4
+// CHECK:   [[V:%[^,=]+]] = alloca [[STRUCT_S]], align 4
+// CHECK:   store i8* %fmt, i8** [[FMT_ADDR]], align 4
+// CHECK:   [[VA1:%[^,=]+]] = bitcast i8** [[VA]] to i8*
+// CHECK:   call void @llvm.va_start(i8* [[VA1]])
+// CHECK:   [[ARGP_CUR:%[^,=]+]] = load i8*, i8** [[VA]], align 4
+// CHECK:   [[ARGP_NEXT:%[^,=]+]] = getelementptr inbounds i8, i8* [[ARGP_CUR]], i32 12
+// CHECK:   store i8* [[ARGP_NEXT]], i8** [[VA]], align 4
+// CHECK:   [[R3:%[^,=]+]] = bitcast i8* [[ARGP_CUR]] to [[STRUCT_S]]*
+// CHECK:   [[R4:%[^,=]+]] = bitcast [[STRUCT_S]]* [[V]] to i8*
+// CHECK:   [[R5:%[^,=]+]] = bitcast [[STRUCT_S]]* [[R3]] to i8*
+// CHECK:   call void @llvm.memcpy.p0i8.p0i8.i32(i8* [[R4]], i8* [[R5]], i32 12, i32 4, i1 false)
+// CHECK:   [[VA2:%[^,=]+]] = bitcast i8** [[VA]] to i8*
+// CHECK:   call void @llvm.va_end(i8* [[VA2]])
+// CHECK:   [[R6:%[^,=]+]] = bitcast [[STRUCT_S]]* %agg.result to i8*
+// CHECK:   [[R7:%[^,=]+]] = bitcast [[STRUCT_S]]* [[V]] to i8*
+// CHECK:   call void @llvm.memcpy.p0i8.p0i8.i32(i8* [[R6]], i8* [[R7]], i32 12, i32 4, i1 false)
+// CHECK:   ret void
+// CHECK: }