But how good has he actually been playing?
Federer has only been pushed to two tiebreakers in 15 sets, winning both by the score 6-3. The Swiss No. 3 seed has handled everything that's been thrown at him, including three consecutive wins over seeded players.
Here are the scorelines for his five matches heading into the semifinals:
1st round vs. Feliciano Lopez: 6-4, 6-3, 7-6(3)
2nd round vs. Maxime Teixeira 6-3, 6-0, 6-2
Round of 32 vs. No. 29 Janko Tipsarevic 6-1, 6-4, 6-3
Round of 16 vs. No. 14 Stanislas Wawrinka 6-3, 6-2, 6-5
Quarterfinals vs. No. 9 Gael Monfils 6-4, 6-3, 7-6(3)
Next up for 16-time Grand Slam champion is Novak Djokovic, who is currently riding a 43-match win streak. Three of his 43 victories have came against Federer, pulling their career series to 13-9 in favor of Federer. Djokovic's three straight wins came after a three-game losing streak to the former No. 1.
Before Federer takes the court to face the Serbian, let's evaluate his performance in Paris thus far.
Roger Federer has only made it to the semifinals at Roland Garros without dropping a set once in his previous 12 appearances. It was 2005, and Federer lost his very next match against Rafael Nadal in four sets.
Two other runs to the quarterfinals without losing a set in 2007 and 2010 didn't end in titles. In 2007, Federer only lost one set in the quarterfinals, but it was Nadal that once again thwarted his championship hopes in the final.
In 2010, Robin Soderling knocked Federer out in the quarterfinals, ending his streak of 23 straight semifinal appearances in major tournaments.
Even in 2009, when Federer won his lone French Open, he lost four sets in before the semifinals. Against Juan Marin del Potro in the semifinals, he surrendered two more sets. He went on to defeat Soderling in the finals in three sets.
Based on past results, Federer is no better off having won every set thus far. Maybe at his age now, he may benefit from more rest, but he's never really been the type to wear down.
Federer may be sweeping through opponents without dropping sets, but he's not playing out of his mind.
Against Monfils, Federer was sluggish to start, trailing 3-1 in the match's early-going. Federer got it together, winning the set 6-4, but it's going to be tough to battle back against Djokovic or Nadal from that deficit.
The thing about Federer's game that's more prevalent these days is the number of mishits and unforced errors that come off his racket. In the past, a Federer mishit was like Halley's Comet—rare. Now, it isn't rare to see Federer end two or three points in a row on basic shots.
The speed of tennis is at an all-time high, and Federer's taking more risks at this stage of his career. His backhand can either be a beautiful thing, or a glaring weakness. Federer is the only player in the top 10 with a one-handed backhand, and it gets picked on by the best players in the world.
However, Federer has hit more winners than errors in all of his matches except his last one. He hit 41 winners against the Frenchman, while committing 42 unforced errors.
For now, Federer seems to have his shanks under control.
Federer's serve needs to be top-notch for him to beat any of players left in the tournament. All three are at the top of the game in returning, which means a lot of second serves for Federer can mean a loss.
Coming into his match with Monfils, Federer's serve was unstoppable. He served above 60 percent in each match, and even hit 70 percent in his destruction of Maxime Teixeira.The wind was an issue in his match with Monfils, causing Federer's serve to dip a little.
However, Federer has only been broken five times in this tournament, and three of those came against Monfils. Maybe even more impressive is the fact that Federer has only faced eight break points.
He leads the last four in the category, as Djokovic has seen nine break chances in just four matches. Nadal and Andy Murray have both encountered more break points than that in a single match.
If Federer keeps serving like he has been, he's going to be tough to break.
Back in his heyday, Federer could win a match by just stepping on the court and putting the ball in play.
His name was so intimidating to some opponents, they would simply spray the ball off the court trying to aim for lines way too early in points. Now, Federer has lost the aura in the early rounds. Every player in the draw sees Federer not as strong as he once was, as he's missing shots that he never used to.
Instead of walking on the court with fear, opponents are strutting out with confidence in hopes they can grind out a win against the 29-year-old. Maybe it doesn't work every time, but players in opening rounds of major tournaments are structuring much better matches against Federer.
Alejandro Falla and Janko Tipsarevic are two players that have earned two sets before Federer in a match in the first three rounds of a slam. Falla actually held a two-sets-to-love lead on Federer at Wimbledon in 2010 before Federer stormed back.
From 2004 to 2009, Federer didn't lose a set in the first round of a Grand Slam, meaning 24 straight first round matches without dropping a set.
Federer needs to bring his best to each match now, as his stranglehold on tennis has been broken.
As mentioned before, Federer has made the transition into a quicker brand of tennis. He's trying to end each point quicker with bigger shots and moves to the net.
Success has resulted so far. Federer has been on court for nine hours and 13 minutes in five matches, which is very impressive in a clay court tournament.
He's also getting the job done at net. The Swiss star is 89-of-123 when he comes up to the net, a conversion rate of 72.4 percent.
If Federer keeps pulling the trigger early in points and connecting, he'll keep Djokovic from controlling all of the points in their match.
Federer needs to remain aggressive if he wants to silence the doubters with a second French Open title.
Everything seems to be going Federer's way right now, but he still has to clean up his game a little if he wants to end Djokovic's tear.
I'm by no means saying that Federer needs to play a perfect match because that's asinine, but he needs to keep his unforced errors below 10 per set, while continuing to go for his shots. Djokovic is an incredible defensive player, and he turns defense into offense in the blink of an eye.
Can Federer beat Djokovic? Absolutely, but he better paint the lines with his serves and stay tight to the lines in rallies, looking for any chance to come to net.
His match against Djokovic can easily be the best of the tournament so far, provided that both players bring their 'A' game.
What grade would you give Federer so far at the French Open?