Commit Graph

6 Commits

Author SHA1 Message Date
Dan Gohman 3c1b3c61e9 Teach two-address lowering how to unfold a load to open up commuting
opportunities. For example, this lets it emit this:

   movq (%rax), %rcx
   addq %rdx, %rcx

instead of this:

   movq %rdx, %rcx
   addq (%rax), %rcx

in the case where %rdx has subsequent uses. It's the same number
of instructions, and usually the same encoding size on x86, but
it appears faster, and in general, it may allow better scheduling
for the load.

llvm-svn: 106493
2010-06-21 22:17:20 +00:00
Dan Gohman 0553acff5e Fix tests to use fadd, fsub, and fmul, instead of add, sub, and mul,
when the type is floating-point.

llvm-svn: 102969
2010-05-03 22:36:46 +00:00
Charles Davis 7e47767763 Add support for the 'alignstack' attribute to the x86 backend. Fixes PR5254.
Also, FileCheck'ize a test.

llvm-svn: 96686
2010-02-19 18:17:13 +00:00
Dan Gohman 40503396da Eliminate more uses of llvm-as and llvm-dis.
llvm-svn: 81290
2009-09-08 23:54:48 +00:00
Dan Gohman a5b9645c4b Split the Add, Sub, and Mul instruction opcodes into separate
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.

For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.

This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt

llvm-svn: 72897
2009-06-04 22:49:04 +00:00
Chris Lattner e30e33af4f Infer alignment of loads and increase their alignment when we can tell they are
from the stack.  This allows us to compile stack-align.ll to:

_test:
	movsd	LCPI1_0, %xmm0
	movapd	%xmm0, %xmm1
***	andpd	4(%esp), %xmm1
	andpd	_G, %xmm0
	addsd	%xmm1, %xmm0
	movl	20(%esp), %eax
	movsd	%xmm0, (%eax)
	ret

instead of:

_test:
	movsd	LCPI1_0, %xmm0
**	movsd	4(%esp), %xmm1
**	andpd	%xmm0, %xmm1
	andpd	_G, %xmm0
	addsd	%xmm1, %xmm0
	movl	20(%esp), %eax
	movsd	%xmm0, (%eax)
	ret

llvm-svn: 46401
2008-01-26 19:45:50 +00:00