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path: root/lib/Transforms/InstCombine/InstCombineCasts.cpp
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2011-04-01Fix build.Benjamin Kramer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128733 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-01InstCombine: Turn icmp + sext into bitwise/integer ops when the input has ↵Benjamin Kramer
only one unknown bit. int test1(unsigned x) { return (x&8) ? 0 : -1; } int test3(unsigned x) { return (x&8) ? -1 : 0; } before (x86_64): _test1: andl $8, %edi cmpl $1, %edi sbbl %eax, %eax ret _test3: andl $8, %edi cmpl $1, %edi sbbl %eax, %eax notl %eax ret after: _test1: shrl $3, %edi andl $1, %edi leal -1(%rdi), %eax ret _test3: shll $28, %edi movl %edi, %eax sarl $31, %eax ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128732 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-01InstCombine: Move (sext icmp) transforms into their own method. No intended ↵Benjamin Kramer
functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128731 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-30Remove PHINode::reserveOperandSpace(). Instead, add a parameter toJay Foad
PHINode::Create() giving the (known or expected) number of operands. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128537 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-30(Almost) always call reserveOperandSpace() on newly created PHINodes.Jay Foad
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128535 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-08llvm.dbg.declare intrinsic does not use any llvm::Values. It's magic!Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127282 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-15convert ConstantVector::get to use ArrayRef.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125537 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-14revert my ConstantVector patch, it seems to have made the llvm-gccChris Lattner
builders unhappy. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125504 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-14Switch ConstantVector::get to use ArrayRef instead of a pointer+sizeChris Lattner
idiom. Change various clients to simplify their code. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125487 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-15implement an instcombine xform that canonicalizes casts outside of ↵Chris Lattner
and-with-constant operations. This fixes rdar://8808586 which observed that we used to compile: union xy { struct x { _Bool b[15]; } x; __attribute__((packed)) struct y { __attribute__((packed)) unsigned long b0to7; __attribute__((packed)) unsigned int b8to11; __attribute__((packed)) unsigned short b12to13; __attribute__((packed)) unsigned char b14; } y; }; struct x foo(union xy *xy) { return xy->x; } into: _foo: ## @foo movq (%rdi), %rax movabsq $1095216660480, %rcx ## imm = 0xFF00000000 andq %rax, %rcx movabsq $-72057594037927936, %rdx ## imm = 0xFF00000000000000 andq %rax, %rdx movzbl %al, %esi orq %rdx, %rsi movq %rax, %rdx andq $65280, %rdx ## imm = 0xFF00 orq %rsi, %rdx movq %rax, %rsi andq $16711680, %rsi ## imm = 0xFF0000 orq %rdx, %rsi movl %eax, %edx andl $-16777216, %edx ## imm = 0xFFFFFFFFFF000000 orq %rsi, %rdx orq %rcx, %rdx movabsq $280375465082880, %rcx ## imm = 0xFF0000000000 movq %rax, %rsi andq %rcx, %rsi orq %rdx, %rsi movabsq $71776119061217280, %r8 ## imm = 0xFF000000000000 andq %r8, %rax orq %rsi, %rax movzwl 12(%rdi), %edx movzbl 14(%rdi), %esi shlq $16, %rsi orl %edx, %esi movq %rsi, %r9 shlq $32, %r9 movl 8(%rdi), %edx orq %r9, %rdx andq %rdx, %rcx movzbl %sil, %esi shlq $32, %rsi orq %rcx, %rsi movl %edx, %ecx andl $-16777216, %ecx ## imm = 0xFFFFFFFFFF000000 orq %rsi, %rcx movq %rdx, %rsi andq $16711680, %rsi ## imm = 0xFF0000 orq %rcx, %rsi movq %rdx, %rcx andq $65280, %rcx ## imm = 0xFF00 orq %rsi, %rcx movzbl %dl, %esi orq %rcx, %rsi andq %r8, %rdx orq %rsi, %rdx ret We now compile this into: _foo: ## @foo ## BB#0: ## %entry movzwl 12(%rdi), %eax movzbl 14(%rdi), %ecx shlq $16, %rcx orl %eax, %ecx shlq $32, %rcx movl 8(%rdi), %edx orq %rcx, %rdx movq (%rdi), %rax ret A small improvement :-) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123520 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-17Whitespace fixes. No functionality change.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122110 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-17Add vector versions of some existing scalar transforms to aid codegen in ↵Nate Begeman
matching psign & pblend operations to the IR produced by clang/gcc for their C idioms. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122105 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-07Fix a serious performance regression introduced by r108687 on linux:Chris Lattner
turning (fptrunc (sqrt (fpext x))) -> (sqrtf x) is great, but we have to delete the original sqrt as well. Not doing so causes us to do two sqrt's when building with -fmath-errno (the default on linux). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113260 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-28for completeness, allow undef also.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112351 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-28handle the constant case of vector insertion. For somethingChris Lattner
like this: struct S { float A, B, C, D; }; struct S g; struct S bar() { struct S A = g; ++A.B; A.A = 42; return A; } we now generate: _bar: ## @bar ## BB#0: ## %entry movq _g@GOTPCREL(%rip), %rax movss 12(%rax), %xmm0 pshufd $16, %xmm0, %xmm0 movss 4(%rax), %xmm2 movss 8(%rax), %xmm1 pshufd $16, %xmm1, %xmm1 unpcklps %xmm0, %xmm1 addss LCPI1_0(%rip), %xmm2 pshufd $16, %xmm2, %xmm2 movss LCPI1_1(%rip), %xmm0 pshufd $16, %xmm0, %xmm0 unpcklps %xmm2, %xmm0 ret instead of: _bar: ## @bar ## BB#0: ## %entry movq _g@GOTPCREL(%rip), %rax movss 12(%rax), %xmm0 pshufd $16, %xmm0, %xmm0 movss 4(%rax), %xmm2 movss 8(%rax), %xmm1 pshufd $16, %xmm1, %xmm1 unpcklps %xmm0, %xmm1 addss LCPI1_0(%rip), %xmm2 movd %xmm2, %eax shlq $32, %rax addq $1109917696, %rax ## imm = 0x42280000 movd %rax, %xmm0 ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112345 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-28optimize bitcasts from large integers to vector into vectorChris Lattner
element insertion from the pieces that feed into the vector. This handles a pattern that occurs frequently due to code generated for the x86-64 abi. We now compile something like this: struct S { float A, B, C, D; }; struct S g; struct S bar() { struct S A = g; ++A.A; ++A.C; return A; } into all nice vector operations: _bar: ## @bar ## BB#0: ## %entry movq _g@GOTPCREL(%rip), %rax movss LCPI1_0(%rip), %xmm1 movss (%rax), %xmm0 addss %xmm1, %xmm0 pshufd $16, %xmm0, %xmm0 movss 4(%rax), %xmm2 movss 12(%rax), %xmm3 pshufd $16, %xmm2, %xmm2 unpcklps %xmm2, %xmm0 addss 8(%rax), %xmm1 pshufd $16, %xmm1, %xmm1 pshufd $16, %xmm3, %xmm2 unpcklps %xmm2, %xmm1 ret instead of icky integer operations: _bar: ## @bar movq _g@GOTPCREL(%rip), %rax movss LCPI1_0(%rip), %xmm1 movss (%rax), %xmm0 addss %xmm1, %xmm0 movd %xmm0, %ecx movl 4(%rax), %edx movl 12(%rax), %esi shlq $32, %rdx addq %rcx, %rdx movd %rdx, %xmm0 addss 8(%rax), %xmm1 movd %xmm1, %eax shlq $32, %rsi addq %rax, %rsi movd %rsi, %xmm1 ret This resolves rdar://8360454 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112343 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-27Implement a pretty general logical shift propagationChris Lattner
framework, which is good at ripping through bitfield operations. This generalize a bunch of the existing xforms that instcombine does, such as (x << c) >> c -> and to handle intermediate logical nodes. This is useful for ripping up the "promote to large integer" code produced by SRoA. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112304 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-27teach the truncation optimization that an entire chain ofChris Lattner
computation can be truncated if it is fed by a sext/zext that doesn't have to be exactly equal to the truncation result type. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112285 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-27Add an instcombine to clean up a common pattern producedChris Lattner
by the SRoA "promote to large integer" code, eliminating some type conversions like this: %94 = zext i16 %93 to i32 ; <i32> [#uses=2] %96 = lshr i32 %94, 8 ; <i32> [#uses=1] %101 = trunc i32 %96 to i8 ; <i8> [#uses=1] This also unblocks other xforms from happening, now clang is able to compile: struct S { float A, B, C, D; }; float foo(struct S A) { return A.A + A.B+A.C+A.D; } into: _foo: ## @foo ## BB#0: ## %entry pshufd $1, %xmm0, %xmm2 addss %xmm0, %xmm2 movdqa %xmm1, %xmm3 addss %xmm2, %xmm3 pshufd $1, %xmm1, %xmm0 addss %xmm3, %xmm0 ret on x86-64, instead of: _foo: ## @foo ## BB#0: ## %entry movd %xmm0, %rax shrq $32, %rax movd %eax, %xmm2 addss %xmm0, %xmm2 movapd %xmm1, %xmm3 addss %xmm2, %xmm3 movd %xmm1, %rax shrq $32, %rax movd %eax, %xmm0 addss %xmm3, %xmm0 ret This seems pretty close to optimal to me, at least without using horizontal adds. This also triggers in lots of other code, including SPEC. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112278 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-26optimize "integer extraction out of the middle of a vector" as producedChris Lattner
by SRoA. This is part of rdar://7892780, but needs another xform to expose this. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112232 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-26optimize bitcast(trunc(bitcast(x))) where the result is a float and 'x'Chris Lattner
is a vector to be a vector element extraction. This allows clang to compile: struct S { float A, B, C, D; }; float foo(struct S A) { return A.A + A.B+A.C+A.D; } into: _foo: ## @foo ## BB#0: ## %entry movd %xmm0, %rax shrq $32, %rax movd %eax, %xmm2 addss %xmm0, %xmm2 movapd %xmm1, %xmm3 addss %xmm2, %xmm3 movd %xmm1, %rax shrq $32, %rax movd %eax, %xmm0 addss %xmm3, %xmm0 ret instead of: _foo: ## @foo ## BB#0: ## %entry movd %xmm0, %rax movd %eax, %xmm0 shrq $32, %rax movd %eax, %xmm2 addss %xmm0, %xmm2 movd %xmm1, %rax movd %eax, %xmm1 addss %xmm2, %xmm1 shrq $32, %rax movd %eax, %xmm0 addss %xmm1, %xmm0 ret ... eliminating half of the horribleness. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112227 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-19Tweak per Chris' comments.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108736 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-19Reimplement r108639 in InstCombine rather than DAGCombine.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108687 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-28Fix instcombine's handling of alloca to accept non-i32 types.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104935 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-25Fix a missing newline in debug output.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104644 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-08Teach instcombine to transform a bitcast/(zext|trunc)/bitcast sequenceChris Lattner
with a vector input and output into a shuffle vector. This sort of sequence happens when the input code stores with one type and reloads with another type and then SROA promotes to i96 integers, which make everyone sad. This fixes rdar://7896024 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103354 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-07Say bitcast instead of bitconvert.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100720 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-16There are two ways of checking for a given type, for example isa<PointerType>(T)Duncan Sands
and T->isPointerTy(). Convert most instances of the first form to the second form. Requested by Chris. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96344 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-15Uniformize the names of type predicates: rather than having isFloatTy andDuncan Sands
isInteger, we now have isFloatTy and isIntegerTy. Requested by Chris! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96223 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-11Rename ValueRequiresCast to ShouldOptimizeCast, to better reflectChris Lattner
what it does. Enhance it to return false to optimizing vector sign extensions from vector comparisions, which is the idiom used to get a splatted vector for a vector comparison. Doing this breaks vector-casts.ll, add some compensating transformations to handle the important case they cover without depending on this canonicalization. This fixes rdar://7434900 a serious pessimization of vector compares. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95855 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02LangRef.html says that inttoptr and ptrtoint always use zero-extensionDan Gohman
when the cast is extending. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95046 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-24change the canonical form of "cond ? -1 : 0" to be Chris Lattner
"sext cond" instead of a select. This simplifies some instcombine code, matches the policy for zext (cond ? 1 : 0 -> zext), and allows us to generate better code for a testcase on ppc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94339 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-18my instcombine transformations to make extension elimination moreChris Lattner
aggressive changed the canonical form from sext(trunc(x)) to ashr(lshr(x)), make sure to transform a couple more things into that canonical form, and catch a case where we missed turning zext/shl/ashr into a single sext. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93787 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11reenable the piece that turns trunc(zext(x)) -> x even if zext has multiple ↵Chris Lattner
uses, codegen has no apparent problem with the trunc version of this, because it turns into a simple subreg idiom git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93202 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11Disable folding sext(trunc(x)) -> x (and other similar cast/cast cases) when ↵Chris Lattner
the trunc has multiple uses. Codegen is not able to coalesce the subreg case correctly and so this leads to higher register pressure and spilling (see PR5997). This speeds up 256.bzip2 from 8.60 -> 8.04s on my machine, ~7%. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93200 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11Extend CanEvaluateZExtd to handle and/or/xor more aggressively in theChris Lattner
BitsToClear case. This allows it to promote expressions which have an and/or/xor after the lshr, promoting cases like test2 (from PR4216) and test3 (random extample extracted from a spec benchmark). clang now compiles the code in PR4216 into: _test_bitfield: ## @test_bitfield movl %edi, %eax orl $194, %eax movl $4294902010, %ecx andq %rax, %rcx orl $32768, %edi andq $39936, %rdi movq %rdi, %rax orq %rcx, %rax ret instead of: _test_bitfield: ## @test_bitfield movl %edi, %eax orl $194, %eax movl $4294902010, %ecx andq %rax, %rcx shrl $8, %edi orl $128, %edi shlq $8, %rdi andq $39936, %rdi movq %rdi, %rax orq %rcx, %rax ret which is still not great, but is progress. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93145 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11Remove the dead TD argument to CanEvaluateZExtd, and add aChris Lattner
new BitsToClear result which allows us to start promoting expressions that end with a lshr-by-constant. This is conservatively correct and better than what we had before (see testcases) but still needs to be extended further. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93144 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11improve comments, remove dead TD argument to CanEvaluateSExtd.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93143 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10teach sext optimization to handle truncs from types that are notChris Lattner
the dest of the sext. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93128 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10teach zext optimization how to deal with truncs that don't come fromChris Lattner
the zext dest type. This allows us to handle test52/53 in cast.ll, and allows llvm-gcc to generate much better code for PR4216 in -m64 mode: _test_bitfield: ## @test_bitfield orl $32962, %edi movl %edi, %eax andl $-25350, %eax ret This also fixes a bug handling vector extends, ensuring that the mask produced is a vector constant, not an integer constant. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93127 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10simplify CanEvaluateSExtd to return a bool now that we have aChris Lattner
simpler profitability predicate. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93111 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10the NumCastsRemoved argument to CanEvaluateSExtd is dead, remove it.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93110 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10now that the cost model has changed, we can always consider Chris Lattner
elimination of a sign extend to be a win, which simplifies the client of CanEvaluateSExtd, and allows us to eliminate more casts (examples taken from real code). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93109 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10change the preferred canonical form for a sign extension to beChris Lattner
lshr+ashr instead of trunc+sext. We want to avoid type conversions whenever possible, it is easier to codegen expressions without truncates and extensions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93107 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10fix pasto that broke bootstrap.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93105 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10simplify CanEvaluateZExtd now that we don't care about the number of Chris Lattner
bits known clear in the result and don't care about the # casts eliminated. TD is also dead but keeping it for now. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93098 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10two changes: Chris Lattner
1) don't try to optimize a sext or zext that is only used by a trunc, let the trunc get optimized first. This avoids some pointless effort in some common cases since instcombine scans down a block in the first pass. 2) Change the cost model for zext elimination to consider an 'and' cheaper than a zext. This allows us to do it more aggressively, and for the next patch to simplify the code quite a bit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93097 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10enhance CanEvaluateZExtd to handle shift left and sext, allowingChris Lattner
more expressions to be promoted and casts eliminated. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93096 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10remove an xform subsumed by EvaluateInDifferentType.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93095 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10clean up this xform by using m_Trunc.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93092 91177308-0d34-0410-b5e6-96231b3b80d8
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