Multiprecision subtraction builtins.

We lower these into 2x chained usub.with.overflow intrinsics.

llvm-svn: 172476

1 files changed, 73 insertions, 0 deletions

diff --git a/clang/test/CodeGen/builtins-multiprecision.c b/clang/test/CodeGen/builtins-multiprecision.c
index 82239d4650a..172f683de3b 100644
--- a/clang/test/CodeGen/builtins-multiprecision.c
+++ b/clang/test/CodeGen/builtins-multiprecision.c
@@ -75,3 +75,76 @@ unsigned long long test_addcll(unsigned long long x, unsigned long long y,
 
   return carryout;
 }
+
+unsigned short test_subcs(unsigned short x, unsigned short y,
+                          unsigned short carryin, unsigned short *z) {
+  // CHECK: @test_subcs
+  // CHECK: %{{.+}} = {{.*}} call { i16, i1 } @llvm.usub.with.overflow.i16(i16 %x, i16 %y)
+  // CHECK: %{{.+}} = extractvalue { i16, i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { i16, i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = {{.*}} call { i16, i1 } @llvm.usub.with.overflow.i16(i16 %{{.+}}, i16 %carryin)
+  // CHECK: %{{.+}} = extractvalue { i16, i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { i16, i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = or i1 %{{.+}}, %{{.+}}
+  // CHECK: %{{.+}} = zext i1 %{{.+}} to i16
+  // CHECK: store i16 %{{.+}}, i16* %z, align 2
+
+  unsigned short carryout;
+  *z = __builtin_subcs(x, y, carryin, &carryout);
+
+  return carryout;
+}
+
+unsigned test_subc(unsigned x, unsigned y, unsigned carryin, unsigned *z) {
+  // CHECK: @test_subc
+  // CHECK: %{{.+}} = {{.*}} call { i32, i1 } @llvm.usub.with.overflow.i32(i32 %x, i32 %y)
+  // CHECK: %{{.+}} = extractvalue { i32, i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { i32, i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = {{.*}} call { i32, i1 } @llvm.usub.with.overflow.i32(i32 %{{.+}}, i32 %carryin)
+  // CHECK: %{{.+}} = extractvalue { i32, i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { i32, i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = or i1 %{{.+}}, %{{.+}}
+  // CHECK: %{{.+}} = zext i1 %{{.+}} to i32
+  // CHECK: store i32 %{{.+}}, i32* %z, align 4
+  unsigned carryout;
+  *z = __builtin_subc(x, y, carryin, &carryout);
+
+  return carryout;
+}
+
+unsigned long test_subcl(unsigned long x, unsigned long y,
+                         unsigned long carryin, unsigned long *z) {
+  // CHECK: @test_subcl([[UL:i32|i64]] %x
+  // CHECK: %{{.+}} = {{.*}} call { [[UL]], i1 } @llvm.usub.with.overflow.[[UL]]([[UL]] %x, [[UL]] %y)
+  // CHECK: %{{.+}} = extractvalue { [[UL]], i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { [[UL]], i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = {{.*}} call { [[UL]], i1 } @llvm.usub.with.overflow.[[UL]]([[UL]] %{{.+}}, [[UL]] %carryin)
+  // CHECK: %{{.+}} = extractvalue { [[UL]], i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { [[UL]], i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = or i1 %{{.+}}, %{{.+}}
+  // CHECK: %{{.+}} = zext i1 %{{.+}} to [[UL]]
+  // CHECK: store [[UL]] %{{.+}}, [[UL]]* %z
+  unsigned long carryout;
+  *z = __builtin_subcl(x, y, carryin, &carryout);
+
+  return carryout;
+}
+
+unsigned long long test_subcll(unsigned long long x, unsigned long long y,
+                               unsigned long long carryin,
+                               unsigned long long *z) {
+  // CHECK: @test_subcll
+  // CHECK: %{{.+}} = {{.*}} call { i64, i1 } @llvm.usub.with.overflow.i64(i64 %x, i64 %y)
+  // CHECK: %{{.+}} = extractvalue { i64, i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { i64, i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = {{.*}} call { i64, i1 } @llvm.usub.with.overflow.i64(i64 %{{.+}}, i64 %carryin)
+  // CHECK: %{{.+}} = extractvalue { i64, i1 } %{{.+}}, 1
+  // CHECK: %{{.+}} = extractvalue { i64, i1 } %{{.+}}, 0
+  // CHECK: %{{.+}} = or i1 %{{.+}}, %{{.+}}
+  // CHECK: %{{.+}} = zext i1 %{{.+}} to i64
+  // CHECK: store i64 %{{.+}}, i64* %z
+  unsigned long long carryout;
+  *z = __builtin_subcll(x, y, carryin, &carryout);
+
+  return carryout;
+}