From: Chris Lattner Date: Sat, 7 Nov 2009 19:11:46 +0000 (+0000) Subject: make instcombine only rewrite a chain of computation X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=918871ee016e9336e28b434738d20960036d05a4;p=oota-llvm.git make instcombine only rewrite a chain of computation (eliminating some extends) if the new type of the computation is legal or if both the source and dest are illegal. This prevents instcombine from changing big chains of computation into i64 on 32-bit targets for example. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86398 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 9d179aea67e..74d0971b422 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -8289,23 +8289,6 @@ Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) { return commonCastTransforms(CI); } -/// isSafeIntegerType - Return true if this is a basic integer type, not a crazy -/// type like i42. We don't want to introduce operations on random non-legal -/// integer types where they don't already exist in the code. In the future, -/// we should consider making this based off target-data, so that 32-bit targets -/// won't get i64 operations etc. -static bool isSafeIntegerType(const Type *Ty) { - switch (Ty->getPrimitiveSizeInBits()) { - case 8: - case 16: - case 32: - case 64: - return true; - default: - return false; - } -} - /// commonIntCastTransforms - This function implements the common transforms /// for trunc, zext, and sext. Instruction *InstCombiner::commonIntCastTransforms(CastInst &CI) { @@ -8334,8 +8317,10 @@ Instruction *InstCombiner::commonIntCastTransforms(CastInst &CI) { // Only do this if the dest type is a simple type, don't convert the // expression tree to something weird like i93 unless the source is also // strange. - if ((isSafeIntegerType(DestTy->getScalarType()) || - !isSafeIntegerType(SrcI->getType()->getScalarType())) && + if (TD && + (TD->isLegalInteger(DestTy->getScalarType()->getPrimitiveSizeInBits()) || + !TD->isLegalInteger((SrcI->getType()->getScalarType() + ->getPrimitiveSizeInBits()))) && CanEvaluateInDifferentType(SrcI, DestTy, CI.getOpcode(), NumCastsRemoved)) { // If this cast is a truncate, evaluting in a different type always @@ -8356,6 +8341,7 @@ Instruction *InstCombiner::commonIntCastTransforms(CastInst &CI) { break; case Instruction::ZExt: { DoXForm = NumCastsRemoved >= 1; + if (!DoXForm && 0) { // If it's unnecessary to issue an AND to clear the high bits, it's // always profitable to do this xform. diff --git a/test/Transforms/InstCombine/2008-01-21-MulTrunc.ll b/test/Transforms/InstCombine/2008-01-21-MulTrunc.ll index a49829af2ee..87c2b75d249 100644 --- a/test/Transforms/InstCombine/2008-01-21-MulTrunc.ll +++ b/test/Transforms/InstCombine/2008-01-21-MulTrunc.ll @@ -1,5 +1,7 @@ ; RUN: opt < %s -instcombine -S | FileCheck %s +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" + define i16 @test1(i16 %a) { %tmp = zext i16 %a to i32 ; [#uses=2] %tmp21 = lshr i32 %tmp, 8 ; [#uses=1] diff --git a/test/Transforms/InstCombine/apint-cast.ll b/test/Transforms/InstCombine/apint-cast.ll index 9bc539ed8b2..85e7a4fca93 100644 --- a/test/Transforms/InstCombine/apint-cast.ll +++ b/test/Transforms/InstCombine/apint-cast.ll @@ -1,6 +1,8 @@ ; Tests to make sure elimination of casts is working correctly ; RUN: opt < %s -instcombine -S | FileCheck %s +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" + define i17 @test1(i17 %a) { %tmp = zext i17 %a to i37 ; [#uses=2] %tmp21 = lshr i37 %tmp, 8 ; [#uses=1] diff --git a/test/Transforms/InstCombine/cast-mul-select.ll b/test/Transforms/InstCombine/cast-mul-select.ll index fcb7e2301d7..dac8c8b128d 100644 --- a/test/Transforms/InstCombine/cast-mul-select.ll +++ b/test/Transforms/InstCombine/cast-mul-select.ll @@ -1,5 +1,7 @@ ; RUN: opt < %s -instcombine -S | FileCheck %s +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" + define i32 @mul(i32 %x, i32 %y) { %A = trunc i32 %x to i8 %B = trunc i32 %y to i8 diff --git a/test/Transforms/InstCombine/cast-set.ll b/test/Transforms/InstCombine/cast-set.ll index 611ded473ef..893440424c4 100644 --- a/test/Transforms/InstCombine/cast-set.ll +++ b/test/Transforms/InstCombine/cast-set.ll @@ -1,6 +1,8 @@ ; This tests for various complex cast elimination cases instcombine should ; handle. +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" + ; RUN: opt < %s -instcombine -S | FileCheck %s define i1 @test1(i32 %X) { diff --git a/test/Transforms/InstCombine/udivrem-change-width.ll b/test/Transforms/InstCombine/udivrem-change-width.ll index 56877e30f9c..9983944df8d 100644 --- a/test/Transforms/InstCombine/udivrem-change-width.ll +++ b/test/Transforms/InstCombine/udivrem-change-width.ll @@ -1,6 +1,8 @@ ; RUN: opt < %s -instcombine -S | not grep zext ; PR4548 +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" + define i8 @udiv_i8(i8 %a, i8 %b) nounwind { %conv = zext i8 %a to i32 %conv2 = zext i8 %b to i32