RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-23 19:23:23 +01:00
Code Issues Projects Releases Wiki Activity

[Reassociate] Don't reassociate when mixing regular and fast-math FP

Browse Source 
instructions.  Inlining might cause such cases and it's not valid to
reassociate floating-point instructions without the unsafe algebra flag.

Patch by Mehdi Amini <mehdi_amini@apple.com>!

llvm-svn: 221462
This commit is contained in:
Chad Rosier 2014-11-06 16:46:37 +00:00
parent c33a78ead1
commit 541e081d90
2 changed files with 27 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
lib/Transforms/Scalar/Reassociate.cpp
View File

@ -237,7 +237,9 @@ FunctionPass *llvm::createReassociatePass() { return new Reassociate(); }
/// opcode and if it only has one use.
static BinaryOperator *isReassociableOp(Value *V, unsigned Opcode) {
if (V->hasOneUse() && isa<Instruction>(V) &&
cast<Instruction>(V)->getOpcode() == Opcode)
cast<Instruction>(V)->getOpcode() == Opcode &&
(!isa<FPMathOperator>(V) ||
cast<Instruction>(V)->hasUnsafeAlgebra()))
return cast<BinaryOperator>(V);
return nullptr;
}
@ -246,7 +248,9 @@ static BinaryOperator *isReassociableOp(Value *V, unsigned Opcode1,
unsigned Opcode2) {
if (V->hasOneUse() && isa<Instruction>(V) &&
(cast<Instruction>(V)->getOpcode() == Opcode1 ||
cast<Instruction>(V)->getOpcode() == Opcode2))
cast<Instruction>(V)->getOpcode() == Opcode2) &&
(!isa<FPMathOperator>(V) ||
cast<Instruction>(V)->hasUnsafeAlgebra()))
return cast<BinaryOperator>(V);
return nullptr;
}
@ -662,7 +666,9 @@ static bool LinearizeExprTree(BinaryOperator *I,
// expression. This means that it can safely be modified. See if we
// can usefully morph it into an expression of the right kind.
assert((!isa<Instruction>(Op) ||
cast<Instruction>(Op)->getOpcode() != Opcode) &&
cast<Instruction>(Op)->getOpcode() != Opcode
|| (isa<FPMathOperator>(Op) &&
!cast<Instruction>(Op)->hasUnsafeAlgebra())) &&
"Should have been handled above!");
assert(Op->hasOneUse() && "Has uses outside the expression tree!");

18
test/Transforms/Reassociate/mixed-fast-nonfast-fp.ll Normal file
View File

@ -0,0 +1,18 @@
; RUN: opt -reassociate %s -S | FileCheck %s
define float @foo(float %a,float %b, float %c) {
; CHECK: %mul3 = fmul float %a, %b
; CHECK-NEXT: fmul fast float %c, 2.000000e+00
; CHECK-NEXT: fadd fast float %factor, %b
; CHECK-NEXT: fmul fast float %tmp1, %a
; CHECK-NEXT: fadd fast float %tmp2, %mul3
; CHECK-NEXT: ret float
%mul1 = fmul fast float %a, %c
%mul2 = fmul fast float %a, %b
%mul3 = fmul float %a, %b
%mul4 = fmul fast float %a, %c
%add1 = fadd fast float %mul1, %mul3
%add2 = fadd fast float %mul4, %mul2
%add3 = fadd fast float %add1, %add2
ret float %add3
}