diff options
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstructionCombining.cpp | 5 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/descale-zero.ll | 20 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/getelementptr.ll | 4 |
3 files changed, 7 insertions, 22 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp index 3b46156c1ab..f62941fbf64 100644 --- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp +++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp @@ -1467,6 +1467,11 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) { // normalized. if (SO1->getType() != GO1->getType()) return nullptr; + // Only do the combine when GO1 and SO1 are both constants. Only in + // this case, we are sure the cost after the merge is never more than + // that before the merge. + if (!isa<Constant>(GO1) || !isa<Constant>(SO1)) + return nullptr; Sum = Builder->CreateAdd(SO1, GO1, PtrOp->getName()+".sum"); } diff --git a/llvm/test/Transforms/InstCombine/descale-zero.ll b/llvm/test/Transforms/InstCombine/descale-zero.ll index 4347be48e61..e69de29bb2d 100644 --- a/llvm/test/Transforms/InstCombine/descale-zero.ll +++ b/llvm/test/Transforms/InstCombine/descale-zero.ll @@ -1,20 +0,0 @@ -; RUN: opt < %s -instcombine -S | FileCheck %s - -target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" -target triple = "x86_64-apple-macosx10.10.0" - -define internal i8* @descale_zero() { -entry: -; CHECK: load i8*, i8** inttoptr (i64 48 to i8**), align 16 -; CHECK-NEXT: ret i8* - %i16_ptr = load i16*, i16** inttoptr (i64 48 to i16**), align 16 - %num = load i64, i64* inttoptr (i64 64 to i64*), align 64 - %num_times_2 = shl i64 %num, 1 - %num_times_2_plus_4 = add i64 %num_times_2, 4 - %i8_ptr = bitcast i16* %i16_ptr to i8* - %i8_ptr_num_times_2_plus_4 = getelementptr i8, i8* %i8_ptr, i64 %num_times_2_plus_4 - %num_times_neg2 = mul i64 %num, -2 - %num_times_neg2_minus_4 = add i64 %num_times_neg2, -4 - %addr = getelementptr i8, i8* %i8_ptr_num_times_2_plus_4, i64 %num_times_neg2_minus_4 - ret i8* %addr -} diff --git a/llvm/test/Transforms/InstCombine/getelementptr.ll b/llvm/test/Transforms/InstCombine/getelementptr.ll index 9bb1b12a697..276ada91f3c 100644 --- a/llvm/test/Transforms/InstCombine/getelementptr.ll +++ b/llvm/test/Transforms/InstCombine/getelementptr.ll @@ -104,8 +104,8 @@ define i32* @test7(i32* %I, i64 %C, i64 %D) { %B = getelementptr i32, i32* %A, i64 %D ret i32* %B ; CHECK-LABEL: @test7( -; CHECK: %A.sum = add i64 %C, %D -; CHECK: getelementptr i32, i32* %I, i64 %A.sum +; CHECK: %A = getelementptr i32, i32* %I, i64 %C +; CHECK: %B = getelementptr i32, i32* %A, i64 %D } define i8* @test8([10 x i32]* %X) { |
