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test commit: remove trailing whitespaces in README.txt 

llvm-svn: 272380
This commit is contained in:
Roger Ferrer Ibanez 2016-06-10 08:19:58 +00:00
parent 0a2f19701e
commit 1efc17e1ec
1 changed files with 8 additions and 8 deletions
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16
llvm/lib/Target/ARM/README.txt
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@ -115,7 +115,7 @@ L6:
.long -858993459
.long 1074318540
3) struct copies appear to be done field by field
3) struct copies appear to be done field by field
instead of by words, at least sometimes:
struct foo { int x; short s; char c1; char c2; };
@ -142,7 +142,7 @@ a good way to measure on ARM).
* Consider this silly example:
double bar(double x) {
double bar(double x) {
double r = foo(3.1);
return x+r;
}
@ -162,7 +162,7 @@ _bar:
fmrrd r0, r1, d0
ldmfd sp!, {r4, r5, r7, pc}
Ignore the prologue and epilogue stuff for a second. Note
Ignore the prologue and epilogue stuff for a second. Note
mov r4, r0
mov r5, r1
the copys to callee-save registers and the fact they are only being used by the
@ -391,10 +391,10 @@ void foo(signed char* p) {
}
llvm decides it's a good idea to turn the repeated if...else into a
binary tree, as if it were a switch; the resulting code requires -1
binary tree, as if it were a switch; the resulting code requires -1
compare-and-branches when *p<=2 or *p==5, the same number if *p==4
or *p>6, and +1 if *p==3. So it should be a speed win
(on balance). However, the revised code is larger, with 4 conditional
(on balance). However, the revised code is larger, with 4 conditional
branches instead of 3.
More seriously, there is a byte->word extend before
@ -421,8 +421,8 @@ int foo(int a, int b, int c, int d) {
return (int)(acc >> 32);
}
Should compile to use SMLAL (Signed Multiply Accumulate Long) which multiplies
two signed 32-bit values to produce a 64-bit value, and accumulates this with
Should compile to use SMLAL (Signed Multiply Accumulate Long) which multiplies
two signed 32-bit values to produce a 64-bit value, and accumulates this with
a 64-bit value.
We currently get this with both v4 and v6:
@ -513,7 +513,7 @@ Be careful though as the last attempt caused infinite looping on lencod.
//===---------------------------------------------------------------------===//
Predication issue. This function:
Predication issue. This function:
extern unsigned array[ 128 ];
int foo( int x ) {