clobber_memory_assembly_test.cc
0b8971075ea9master

clobber_memory_assembly_test.cc
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			#include <benchmark/benchmark.h>

			#ifdef __clang__
			#pragma clang diagnostic ignored "-Wreturn-type"
			#endif

			extern "C" {

			extern int ExternInt;
			extern int ExternInt2;
			extern int ExternInt3;
			}

			// CHECK-LABEL: test_basic:
			extern "C" void test_basic() {
			int x;
			benchmark::DoNotOptimize(&x);
			x = 101;
			benchmark::ClobberMemory();
			// CHECK: leaq [[DEST:[^,]+]], %rax
			// CHECK: movl $101, [[DEST]]
			// CHECK: ret
			}

			// CHECK-LABEL: test_redundant_store:
			extern "C" void test_redundant_store() {
			ExternInt = 3;
			benchmark::ClobberMemory();
			ExternInt = 51;
			// CHECK-DAG: ExternInt
			// CHECK-DAG: movl $3
			// CHECK: movl $51
			}

			// CHECK-LABEL: test_redundant_read:
			extern "C" void test_redundant_read() {
			int x;
			benchmark::DoNotOptimize(&x);
			x = ExternInt;
			benchmark::ClobberMemory();
			x = ExternInt2;
			// CHECK: leaq [[DEST:[^,]+]], %rax
			// CHECK: ExternInt(%rip)
			// CHECK: movl %eax, [[DEST]]
			// CHECK-NOT: ExternInt2
			// CHECK: ret
			}

			// CHECK-LABEL: test_redundant_read2:
			extern "C" void test_redundant_read2() {
			int x;
			benchmark::DoNotOptimize(&x);
			x = ExternInt;
			benchmark::ClobberMemory();
			x = ExternInt2;
			benchmark::ClobberMemory();
			// CHECK: leaq [[DEST:[^,]+]], %rax
			// CHECK: ExternInt(%rip)
			// CHECK: movl %eax, [[DEST]]
			// CHECK: ExternInt2(%rip)
			// CHECK: movl %eax, [[DEST]]
			// CHECK: ret
			}