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| author | Juergen Ributzka <juergen@apple.com> | 2014-04-02 21:45:36 +0000 |
|---|---|---|
| committer | Juergen Ributzka <juergen@apple.com> | 2014-04-02 21:45:36 +0000 |
| commit | 27435b3b8ac6dbc8247bd32a709b78740daaa040 (patch) | |
| tree | 9ccac55e46b4f48ae419ba2ad1bf3833afa491d7 | |
| parent | 7ad0b88396522d4abf3973cd95d2f28f40af7b54 (diff) | |
| download | bcm5719-llvm-27435b3b8ac6dbc8247bd32a709b78740daaa040.tar.gz bcm5719-llvm-27435b3b8ac6dbc8247bd32a709b78740daaa040.zip | |
Add comments and test case for [X86TTI] Make constant base pointers for GetElementPtr opaque (r204739).
llvm-svn: 205468
| -rw-r--r-- | llvm/lib/Target/X86/X86TargetTransformInfo.cpp | 3 | ||||
| -rw-r--r-- | llvm/test/Transforms/ConstantHoisting/X86/const-base-addr.ll | 24 |
2 files changed, 27 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp index 437f63d3280..c04964d60bf 100644 --- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp +++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp @@ -915,6 +915,9 @@ unsigned X86TTI::getIntImmCost(unsigned Opcode, unsigned Idx, const APInt &Imm, switch (Opcode) { default: return TCC_Free; case Instruction::GetElementPtr: + // Always hoist the base address of a GetElementPtr. This prevents the + // creation of new constants for every base constant that gets constant + // folded with the offset. if (Idx == 0) return 2 * TCC_Basic; return TCC_Free; diff --git a/llvm/test/Transforms/ConstantHoisting/X86/const-base-addr.ll b/llvm/test/Transforms/ConstantHoisting/X86/const-base-addr.ll new file mode 100644 index 00000000000..ffd51b5c068 --- /dev/null +++ b/llvm/test/Transforms/ConstantHoisting/X86/const-base-addr.ll @@ -0,0 +1,24 @@ +; RUN: opt -S -consthoist < %s | FileCheck %s + +target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-apple-macosx10.9.0" + +%T = type { i32, i32, i32, i32 } + +; Test if even cheap base addreses are hoisted. +define i32 @test1() nounwind { +; CHECK-LABEL: @test1 +; CHECK: %const = bitcast i32 12345678 to i32 +; CHECK: %1 = inttoptr i32 %const to %T* +; CHECK: %addr1 = getelementptr %T* %1, i32 0, i32 1 + %addr1 = getelementptr %T* inttoptr (i32 12345678 to %T*), i32 0, i32 1 + %tmp1 = load i32* %addr1 + %addr2 = getelementptr %T* inttoptr (i32 12345678 to %T*), i32 0, i32 2 + %tmp2 = load i32* %addr2 + %addr3 = getelementptr %T* inttoptr (i32 12345678 to %T*), i32 0, i32 3 + %tmp3 = load i32* %addr3 + %tmp4 = add i32 %tmp1, %tmp2 + %tmp5 = add i32 %tmp3, %tmp4 + ret i32 %tmp5 +} + |
