| ; RUN: opt -S -passes=gvn < %s | FileCheck %s |
| ; Check that loads from calloc are recognized as being zero. |
| |
| target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" |
| |
| ; Function Attrs: nounwind uwtable |
| define i32 @test1() { |
| %1 = tail call noalias ptr @calloc(i64 1, i64 4) |
| ; This load is trivially constant zero |
| %2 = load i32, ptr %1, align 4 |
| ret i32 %2 |
| |
| ; CHECK-LABEL: @test1( |
| ; CHECK-NOT: %2 = load i32, ptr %1, align 4 |
| ; CHECK: ret i32 0 |
| |
| ; CHECK_NO_LIBCALLS-LABEL: @test1( |
| ; CHECK_NO_LIBCALLS: load |
| ; CHECK_NO_LIBCALLS: ret i32 % |
| |
| } |
| |
| define i32 @as_invoke(i1 %c) personality ptr undef { |
| bb3: |
| %mem = invoke noalias ptr @calloc(i64 1, i64 4) |
| to label %bb4 unwind label %bb1 |
| |
| bb1: |
| %lp = landingpad { ptr, i32 } cleanup |
| ret i32 0 |
| |
| bb4: |
| ; This load is trivially constant zero |
| %res = load i32, ptr %mem, align 4 |
| ret i32 %res |
| |
| ; CHECK-LABEL: @as_invoke( |
| ; CHECK-NOT: %3 = load i32, ptr %2, align 4 |
| ; CHECK: ret i32 0 |
| |
| ; CHECK_NO_LIBCALLS-LABEL: @as_invoke( |
| ; CHECK_NO_LIBCALLS: load |
| ; CHECK_NO_LIBCALLS: ret i32 % |
| } |
| |
| declare noalias ptr @calloc(i64, i64) allockind("alloc,zeroed") allocsize(0,1) |
